Android工作室获得跳帧错误和应用程序无响应对话框

Question

我是android studio(Android App Development(的新手。

在开发安卓应用程序时遇到问题。获取以下错误

"Skipped 3 frames! The application may be doing too much work on its main thread."

并显示对话框"application not responding".

我正在使用sqlite数据库创建/写入xml文件到外部存储。

请帮我如何解决这个问题？

数据库助手.java

package com.techyour.bank;
import android.content.ContentValues;
import android.content.Context;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;
import java.util.ArrayList;
import java.util.List;
public class DbHelper extends SQLiteOpenHelper {
private SQLiteDatabase db;
public static final String DB_NAME = "my_bank_data.db";
private static final int DB_VERSION = 1;
public static final String TABLE_NAME = "my_banks";
public static final String _ID = "_id";
public static final String NAME = "name";
public static final String AGE = "age";
public static final String GENDER = "gender";
public static final String DOB = "dob";
public static final String COUNTRY = "country";
public static final String PH_NO = "ph_no";

public DbHelper(Context context) {
super(context, DB_NAME, null, DB_VERSION);
}
@Override
public void onCreate(SQLiteDatabase db) {
this.db = db;
final String CREATE_TABLE = "CREATE TABLE " + TABLE_NAME +
" ( " +
_ID + " INTEGER PRIMARY KEY AUTOINCREMENT, " +
NAME + " TEXT, " +
AGE + " TEXT, " +
GENDER + " TEXT, " +
DOB + " TEXT, " +
COUNTRY + " TEXT, " +
PH_NO + " TEXT " +
")";
db.execSQL(CREATE_TABLE);
defaultData();
}
@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
db.execSQL("DROP TABLE IF EXISTS " + TABLE_NAME);
onCreate(db);
}
private void defaultData() {
GetSet a1 = new GetSet("Alice", "20", "Male", "1994", "USA", "9876543210");
defaultData2(a1);
GetSet a2 = new GetSet("Bob", "21", "Male", "1997", "UK", "4002639610");
defaultData2(a2);
GetSet a3 = new GetSet("Eve", "22", "Male", "1964", "INDIA", "7040576498");
defaultData2(a3);
GetSet a4 = new GetSet("Mildred Martin", "23", "Male", "1959", "USA", "2113309849");
defaultData2(a4);
GetSet a5 = new GetSet("Ruth    Hill", "24", "Male", "1918", "USA", "6296713680");
defaultData2(a5);
GetSet a6 = new GetSet("Justin  Baker", "25", "Male", "1976", "USA", "5113788645");
defaultData2(a6);
GetSet a7 = new GetSet("Carl    Coleman", "26", "Male", "1945", "USA", "9346135599");
defaultData2(a7);
GetSet a8 = new GetSet("Wanda   Mitchell", "27", "Male", "1909", "USA", "9134105633");
defaultData2(a8);
GetSet a9 = new GetSet("Joe Bennett", "28", "Male", "1915", "UK", "6383446319");
defaultData2(a9);
GetSet a10 = new GetSet("Willie Carter", "29", "Male", "1958", "USA", "5578230822");
defaultData2(a10);
GetSet a11 = new GetSet("Debra  Bryant", "21", "Male", "1980", "USA", "4818754159");
defaultData2(a11);
GetSet a12 = new GetSet("Christopher    Powell", "20", "Male", "1913", "USA", "0403170292");
defaultData2(a12);
GetSet a13 = new GetSet("Gloria Moore", "30", "Male", "1947", "USA", "5206569101");
defaultData2(a13);
GetSet a14 = new GetSet("Beverly    Nelson", "20", "Male", "1905", "UK", "9449903813");
defaultData2(a14);
GetSet a15 = new GetSet("Melissa    Davis", "22", "Female", "1955", "USA", "5961002003");
defaultData2(a15);
GetSet a16 = new GetSet("Janet  Price", "17", "Male", "1935", "USA", "1977492463");
defaultData2(a16);
GetSet a17 = new GetSet("Helen  Edwards", "20", "Male", "1910", "USA", "6834805918");
defaultData2(a17);
GetSet a18 = new GetSet("Craig  Garcia", "23", "Male", "1911", "INDIA", "0807332318");
defaultData2(a18);
GetSet a19 = new GetSet("Deborah    Jenkins", "20", "Male", "1935", "USA", "0068416390");
defaultData2(a19);
GetSet a20 = new GetSet("Tina   Stewart", "20", "Female", "1963", "USA", "1054983413");
defaultData2(a20);
GetSet a21 = new GetSet("Kimberly   Howard", "31", "Male", "1911", "USA", "9852591520");
defaultData2(a21);
GetSet a22 = new GetSet("Earl   Bailey", "20", "Male", "1948", "USA", "9546632144");
defaultData2(a22);
GetSet a23 = new GetSet("Wayne  Hernandez", "28", "Female", "1900", "INDIA", "9837178563");
defaultData2(a23);
GetSet a24 = new GetSet("Terry  Cook", "18", "Male", "1910", "USA", "8298923456");
defaultData2(a24);
GetSet a25 = new GetSet("Ronald Evans", "20", "Male", "1994", "USA", "4541427090");
defaultData2(a25);
GetSet a26 = new GetSet("Doris  Brooks", "20", "Male", "1958", "INDIA", "0960421257");
defaultData2(a26);
GetSet a27 = new GetSet("Sarah  Simmons", "19", "Female", "1982", "USA", "5305824976");
defaultData2(a27);
GetSet a28 = new GetSet("Frank  Thompson", "26", "Male", "1973", "USA", "9079724716");
defaultData2(a28);
GetSet a29 = new GetSet("Smith", "20", "Male", "1954", "USA", "6300051365");
defaultData2(a29);
GetSet a30 = new GetSet("Jhon", "27", "Male", "1989", "UK", "4545983296");
defaultData2(a30);
}
private void defaultData2(GetSet getSet) {
ContentValues cv = new ContentValues();
cv.put(NAME, getSet.getNAME());
cv.put(AGE, getSet.getAGE());
cv.put(GENDER, getSet.getGENDER());
cv.put(DOB, getSet.getDOB());
cv.put(COUNTRY, getSet.getCOUNTRY());
cv.put(PH_NO, getSet.getPH_NO());
db.insert(TABLE_NAME, null, cv);
}
public List<GetSet> getAllData(String where) {
List<GetSet> list = new ArrayList<>();
db = getReadableDatabase();
String[] selectionArgs = new String[]{where};
Cursor c = db.rawQuery("SELECT * FROM " + TABLE_NAME +
" WHERE " + _ID + " = ?", selectionArgs);
if (c.moveToFirst()) {
do {
GetSet getSet = new GetSet();
getSet.setNAME(c.getString(c.getColumnIndex(NAME)));
getSet.setAGE(c.getString(c.getColumnIndex(AGE)));
getSet.setGENDER(c.getString(c.getColumnIndex(GENDER)));
getSet.setDOB(c.getString(c.getColumnIndex(DOB)));
getSet.setCOUNTRY(c.getString(c.getColumnIndex(COUNTRY)));
getSet.setPH_NO(c.getString(c.getColumnIndex(PH_NO)));
list.add(getSet);
} while (c.moveToNext());
}
c.close();
return list;
}
public List<GetSet> getDataCount() {
List<GetSet> list2 = new ArrayList<>();
db = getReadableDatabase();
Cursor c = db.rawQuery("SELECT * FROM " + TABLE_NAME +
" WHERE " + NAME + " IS NOT NULL ", null);
if (c.moveToFirst()) {
do {
GetSet getSet = new GetSet();
getSet.setNAME(c.getString(c.getColumnIndex(NAME)));
list2.add(getSet);
} while (c.moveToNext());
}
c.close();
return list2;
}
public Cursor getDataById(String id) {
SQLiteDatabase db = this.getWritableDatabase();
Cursor cursor = db.rawQuery("SELECT * FROM " + TABLE_NAME +
" WHERE " + _ID + " = ?", new String[]{id});
return cursor;
}
}

主活动.java

package com.techyour.bank;
import android.Manifest;
import android.content.pm.PackageManager;
import android.os.Environment;
import android.support.v4.app.ActivityCompat;
import android.support.v4.content.ContextCompat;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.util.Xml;
import android.view.View;
import android.widget.TextView;
import android.widget.Toast;
import org.xmlpull.v1.XmlSerializer;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.StringWriter;
import java.util.List;
public class MainActivity extends AppCompatActivity {
TextView tvData;
DbHelper dbHelper;
GetSet getSet;
List<GetSet> dataList;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
dbHelper = new DbHelper(this);
dbHelper.getWritableDatabase();
tvData = findViewById(R.id.tvData);
checkPermission();
}
private void checkPermission() {
if (ContextCompat.checkSelfPermission(this, Manifest.permission.WRITE_EXTERNAL_STORAGE) != PackageManager.PERMISSION_GRANTED) {
ActivityCompat.requestPermissions(this, new String[]{android.Manifest.permission.WRITE_EXTERNAL_STORAGE}, 1);
}
}
public void ocBtnGetSet(View view) throws IOException {
XmlSerializer xmlSerializer = Xml.newSerializer();
StringWriter writer = new StringWriter();
try {
xmlSerializer.setOutput(writer);
xmlSerializer.startDocument("UTF-8", true);
xmlSerializer.setFeature("http://xmlpull.org/v1/doc/features.html#indent-output", true);
xmlSerializer.startTag("", "persons");
} catch (IOException e) {
e.printStackTrace();
}
for (int i = 1; i <= dbHelper.getDataCount().size(); i++) {
dataList = dbHelper.getAllData(String.valueOf(i));
getSet = dataList.get(0);
try {
xmlSerializer.startTag("", "person");
xmlSerializer.startTag("", "name");
xmlSerializer.text(getSet.getNAME());
xmlSerializer.endTag("", "name");
xmlSerializer.startTag("", "age");
xmlSerializer.text(getSet.getAGE());
xmlSerializer.endTag("", "age");
xmlSerializer.startTag("", "gender");
xmlSerializer.text(getSet.getGENDER());
xmlSerializer.endTag("", "gender");
xmlSerializer.startTag("", "dob");
xmlSerializer.text(getSet.getDOB());
xmlSerializer.endTag("", "dob");
xmlSerializer.startTag("", "country");
xmlSerializer.text(getSet.getCOUNTRY());
xmlSerializer.endTag("", "country");
xmlSerializer.startTag("", "ph_no");
xmlSerializer.text(getSet.getPH_NO());
xmlSerializer.endTag("", "ph_no");
xmlSerializer.endTag("", "person");
} catch (IOException e) {
e.printStackTrace();
}
}
xmlSerializer.endTag("", "persons");
xmlSerializer.endDocument();
tvData.append(writer.toString());
writeXmlToSd(writer.toString());
}
private void writeXmlToSd(String data) {
String state = Environment.getExternalStorageState();
if (Environment.MEDIA_MOUNTED.equals(state)) {
File Root = Environment.getExternalStorageDirectory();
File Dir = new File(Root.getAbsolutePath() + "/AABBCC");
if (!Dir.exists()) {
Dir.mkdir();
}
File file = new File(Dir, "backup.xml");
String text = data;
try {
FileOutputStream fos = new FileOutputStream(file);
fos.write(text.getBytes());
fos.close();
Toast.makeText(this, "Backup Success", Toast.LENGTH_SHORT).show();
} catch (FileNotFoundException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
} else {
Toast.makeText(this, "SD Card Not Found", Toast.LENGTH_SHORT).show();
}
}
}

获取集.java

package com.techyour.bank;
/**
* Created by Vamshi Krishna on 01-10-2018 001.
*/
class GetSet {
private String NAME;
private String AGE;
private String GENDER;
private String DOB;
private String COUNTRY;
private String PH_NO;
GetSet() {
}
public GetSet(String NAME, String AGE, String GENDER, String DOB, String COUNTRY, String PH_NO) {
this.NAME = NAME;
this.AGE = AGE;
this.GENDER = GENDER;
this.DOB = DOB;
this.COUNTRY = COUNTRY;
this.PH_NO = PH_NO;
}
public String getNAME() {
return NAME;
}
public void setNAME(String NAME) {
this.NAME = NAME;
}
public String getAGE() {
return AGE;
}
public void setAGE(String AGE) {
this.AGE = AGE;
}
public String getGENDER() {
return GENDER;
}
public void setGENDER(String GENDER) {
this.GENDER = GENDER;
}
public String getDOB() {
return DOB;
}
public void setDOB(String DOB) {
this.DOB = DOB;
}
public String getCOUNTRY() {
return COUNTRY;
}
public void setCOUNTRY(String COUNTRY) {
this.COUNTRY = COUNTRY;
}
public String getPH_NO() {
return PH_NO;
}
public void setPH_NO(String PH_NO) {
this.PH_NO = PH_NO;
}
}

activity_main.xml

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:padding="6dp"
tools:context="com.techyour.bank.MainActivity">
<Button
android:id="@+id/btnGetSet"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:onClick="ocBtnGetSet"
android:text="Get" />
<ScrollView
android:id="@+id/sv"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_below="@+id/btnGetSet">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical">
<TextView
android:id="@+id/tvData"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:textSize="20sp" />
</LinearLayout>
</ScrollView>
</RelativeLayout>

代码已更新(主活动.java(，但收到相同的错误

package com.techyour.bank;
import android.Manifest;
import android.content.pm.PackageManager;
import android.os.AsyncTask;
import android.os.Environment;
import android.support.v4.app.ActivityCompat;
import android.support.v4.content.ContextCompat;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.util.Xml;
import android.view.View;
import android.widget.TextView;
import android.widget.Toast;
import org.xmlpull.v1.XmlSerializer;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.StringWriter;
import java.util.List;
public class MainActivity extends AppCompatActivity {
DbHelper dbHelper;
GetSet getSet;
List<GetSet> dataList;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
dbHelper = new DbHelper(this);
dbHelper.getWritableDatabase();
checkPermission();
}
private void checkPermission() {
if (ContextCompat.checkSelfPermission(this, Manifest.permission.WRITE_EXTERNAL_STORAGE) != PackageManager.PERMISSION_GRANTED) {
ActivityCompat.requestPermissions(this, new String[]{android.Manifest.permission.WRITE_EXTERNAL_STORAGE}, 1);
}
}
public void ocBtnGetSet(View view) throws IOException {
new MyTask().execute();
}
private void writeXmlToSd(String data) {
String state = Environment.getExternalStorageState();
if (Environment.MEDIA_MOUNTED.equals(state)) {
File Root = Environment.getExternalStorageDirectory();
File Dir = new File(Root.getAbsolutePath() + "/AABBCC");
if (!Dir.exists()) {
Dir.mkdir();
}
File file = new File(Dir, "backup.xml");
String text = data;
try {
FileOutputStream fos = new FileOutputStream(file);
fos.write(text.getBytes());
fos.close();
Toast.makeText(this, "Backup Success", Toast.LENGTH_SHORT).show();
} catch (FileNotFoundException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
} else {
Toast.makeText(this, "SD Card Not Found", Toast.LENGTH_SHORT).show();
}
}

private class MyTask extends AsyncTask<Void, Void, String> {
TextView tvData;
@Override
protected String doInBackground(Void... voids) {
tvData = findViewById(R.id.tvData);
XmlSerializer xmlSerializer = Xml.newSerializer();
StringWriter writer = new StringWriter();
try {
xmlSerializer.setOutput(writer);
xmlSerializer.startDocument("UTF-8", true);
xmlSerializer.setFeature("http://xmlpull.org/v1/doc/features.html#indent-output", true);
xmlSerializer.startTag("", "persons");
} catch (IOException e) {
e.printStackTrace();
}
for (int i = 1; i <= dbHelper.getDataCount().size(); i++) {
dataList = dbHelper.getAllData(String.valueOf(i));
getSet = dataList.get(0);
try {
xmlSerializer.startTag("", "person");
xmlSerializer.startTag("", "name");
xmlSerializer.text(getSet.getNAME());
xmlSerializer.endTag("", "name");
xmlSerializer.startTag("", "age");
xmlSerializer.text(getSet.getAGE());
xmlSerializer.endTag("", "age");
xmlSerializer.startTag("", "gender");
xmlSerializer.text(getSet.getGENDER());
xmlSerializer.endTag("", "gender");
xmlSerializer.startTag("", "dob");
xmlSerializer.text(getSet.getDOB());
xmlSerializer.endTag("", "dob");
xmlSerializer.startTag("", "country");
xmlSerializer.text(getSet.getCOUNTRY());
xmlSerializer.endTag("", "country");
xmlSerializer.startTag("", "ph_no");
xmlSerializer.text(getSet.getPH_NO());
xmlSerializer.endTag("", "ph_no");
xmlSerializer.endTag("", "person");
} catch (IOException e) {
e.printStackTrace();
}
}
try {
xmlSerializer.endTag("", "persons");
xmlSerializer.endDocument();
} catch (IOException e) {
e.printStackTrace();
}
return writer.toString();
}
@Override
protected void onPreExecute() {
super.onPreExecute();
}
@Override
protected void onPostExecute(String aVoid) {
tvData.setText(aVoid);
writeXmlToSd(aVoid);
Toast.makeText(MainActivity.this, "SUCCESS", Toast.LENGTH_SHORT).show();
}
@Override
protected void onProgressUpdate(Void... values) {
super.onProgressUpdate(values);
}
}
}

Answer 1

您实际上在主线程中做了很多工作。主线程运行应用的所有用户界面工作。 请考虑在单独的线程中运行数据库代码。

您可以在开发人员文档中找到有关线程的更多信息

，请访问 https://developer.android.com/guide/components/processes-and-threads如果将该工作卸载到线程，请确保 UI 告知用户后台正在进行工作，以便用户不会放弃屏幕。

Answer 2

将所有繁重的工作转移到 AsyncTask

使异步任务像，

class MyTask extends AsyncTask<Void, Void, Void> {
@Override
protected Void doInBackground(Void... voids) {
XmlSerializer xmlSerializer = Xml.newSerializer();
StringWriter writer = new StringWriter();
try {
xmlSerializer.setOutput(writer);
xmlSerializer.startDocument("UTF-8", true);
xmlSerializer.setFeature("http://xmlpull.org/v1/doc/features.html#indent-output", true);
xmlSerializer.startTag("", "persons");
} catch (IOException e) {
e.printStackTrace();
}
for (int i = 1; i <= dbHelper.getDataCount().size(); i++) {
dataList = dbHelper.getAllData(String.valueOf(i));
getSet = dataList.get(0);
try {
xmlSerializer.startTag("", "person");
xmlSerializer.startTag("", "name");
xmlSerializer.text(getSet.getNAME());
xmlSerializer.endTag("", "name");
xmlSerializer.startTag("", "age");
xmlSerializer.text(getSet.getAGE());
xmlSerializer.endTag("", "age");
xmlSerializer.startTag("", "gender");
xmlSerializer.text(getSet.getGENDER());
xmlSerializer.endTag("", "gender");
xmlSerializer.startTag("", "dob");
xmlSerializer.text(getSet.getDOB());
xmlSerializer.endTag("", "dob");
xmlSerializer.startTag("", "country");
xmlSerializer.text(getSet.getCOUNTRY());
xmlSerializer.endTag("", "country");
xmlSerializer.startTag("", "ph_no");
xmlSerializer.text(getSet.getPH_NO());
xmlSerializer.endTag("", "ph_no");
xmlSerializer.endTag("", "person");
} catch (IOException e) {
e.printStackTrace();
}
}
xmlSerializer.endTag("", "persons");
xmlSerializer.endDocument();
tvData.append(writer.toString());
writeXmlToSd(writer.toString());
return null;
}
}

然后通过调用在单击函数中执行任务

new MyTask().execute();

Answer 3

<Button
android:id="@+id/btnGetSet"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:onClick="ocBtnGetSet"
android:text="Get" />

ocBtnGetSet

上面的功能正在制造问题。因为在此函数中，您正在执行数据库操作。

您正在主线程上执行繁重的操作。基本上是安卓应用程序在一个主线程上。如果你想要像数据库这样的繁重操作或调用 API 来获取数据。您可以使用AsyncTask.它与主线程分开运行。