>我有一个自定义ListView BaseAdapter.在此自定义ListView当用户单击任何特定文本时，它会说出文本，但问题是当任何用户单击后退按钮时，如何从BaseAdapter中停止此文本。我知道如何停止Activity但不知道如何在用户按下后退按钮时停止BaseAdapter。这是我的代码：
package bible.swordof.God;
import android.app.Activity;
import android.content.ContentValues;
import android.content.Context;
import android.content.Intent;
import android.content.SharedPreferences;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.graphics.Color;
import android.os.Vibrator;
import android.speech.tts.TextToSpeech;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.CompoundButton;
import android.widget.ImageView;
import android.widget.LinearLayout;
import android.widget.TextView;
import android.widget.Toast;
import android.widget.ToggleButton;
import java.util.ArrayList;
import java.util.List;
import java.util.Locale;
import java.util.zip.Inflater;
import es.dmoral.toasty.Toasty;
import petrov.kristiyan.colorpicker.ColorPicker;
import static android.content.Context.MODE_PRIVATE;
public class BaseAdopter extends BaseAdapter implements TextToSpeech.OnInitListener{
public BaseAdopter(Context context, List<String> versenumber, List<String> verseid, List<String> verselist, List<String> refernce) {
this.context = context;
this.versenumber = versenumber;
this.verseid = verseid;
this.verselist = verselist;
this.refernce = refernce;
}
ALLVERSE allverse;
ArrayList<String> colors;
private Context context;
private List<String> versenumber;
private List<String>verseid;
private List<String> verselist;
private List<String> refernce;
TextToSpeech textToSpeech;
private DatabaseHelper mDBHelper;
private SQLiteDatabase mDb;
@Override
public int getCount() {
return versenumber.size();
}
@Override
public Object getItem(int position) {
return null;
}
@Override
public long getItemId(int position) {
return 0;
}
@Override
public View getView(final int position, View convertView, ViewGroup parent) {
LayoutInflater inflater = (LayoutInflater)context.getSystemService(Activity.LAYOUT_INFLATER_SERVICE);
View view=inflater.inflate(R.layout.versedisplayrow,parent,false);
textToSpeech = new TextToSpeech(context, this);
final TextView verseno;
final TextView verselistview;
ImageView share;
ToggleButton addfavoruite;
ImageView speakverse;
final LinearLayout linearLayout;
verseno=(TextView)view.findViewById(R.id.versenumber);
verseno.setText(versenumber.get(position));
verselistview=(TextView)view.findViewById(R.id.verse);
verselistview.setText(verselist.get(position));
addfavoruite=(ToggleButton)view.findViewById(R.id.adbookmark);
linearLayout=(LinearLayout)view.findViewById(R.id.layout);
share=(ImageView)view.findViewById(R.id.share);
speakverse=(ImageView)view.findViewById(R.id.speak);
if(DefaultSettings.nightmode(context)){
linearLayout.setBackgroundColor(Color.parseColor("#363437"));
verselistview.setTextColor(Color.parseColor("#ffffff"));
verseno.setTextColor(Color.parseColor("#ffffff"));
}
speakverse.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
singleverse(verselist.get(position).toString());
}
});
int a=position+1;
colors=new ArrayList<>();
colors.add("#e0e0eb");
colors.add("#ccffff");
colors.add("#ffe6ff");
colors.add("#ffffcc");
colors.add("#ccffcc");
colors.add("#e6f2ff");
SharedPreferences sharedPreferences=context.getSharedPreferences("DATA",MODE_PRIVATE);
int getverse=sharedPreferences.getInt("versenumber",1);
if(a==getverse){
if(DefaultSettings.highlight(context)){
DefaultSettings.color(context);
linearLayout.setBackgroundColor(DefaultSettings.colorpicked);
}
}
if(Checkisfavourite("favourite","id",verseid.get(position)))
{
if(verseid.get(position).equals(verseid.get(position))){
addfavoruite.setChecked(true);
}else {
addfavoruite.setChecked(false);
}
}
addfavoruite.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() {
@Override
public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
if(isChecked){
mDBHelper = new DatabaseHelper(context);
mDb = mDBHelper.getWritableDatabase();
ContentValues contentValues=new ContentValues();
contentValues.put("id",verseid.get(position));
contentValues.put("bookname",refernce.get(position));
contentValues.put("versenumber",versenumber.get(position));
contentValues.put("verse",verselist.get(position));
long check=mDb.insert("favourite",null,contentValues);
Toasty.success(context, "Added in favouite", Toast.LENGTH_SHORT, true).show();
}
else {
mDBHelper = new DatabaseHelper(context);
mDb = mDBHelper.getWritableDatabase();
long delete= mDb.delete("favourite","id=?",new String[]{verseid.get(position)});
Toasty.error(context, "Remove in favouite", Toast.LENGTH_SHORT, true).show();
}
}
});
share.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
Toasty.info(context, "Sharing a verse.", Toast.LENGTH_SHORT, true).show();
Intent sendIntent = new Intent();
sendIntent.setAction(Intent.ACTION_SEND);
sendIntent.putExtra(Intent.EXTRA_TEXT, refernce.get(position) + ":" + versenumber.get(position) + 'n' + verselist.get(position) +
+'n' +'n' +'n' +"https://play.google.com/store/apps/details?id=bible.swordof.God");
sendIntent.setType("text/plain");
context.startActivity(sendIntent);
}
});
/* linearLayout.setOnLongClickListener(new View.OnLongClickListener() {
@Override
public boolean onLongClick(View v) {
//Toasty.success(activity, "PICK COLOR", Toast.LENGTH_SHORT, true).show();
Vibrator vibe = (Vibrator)context.getSystemService(Context.VIBRATOR_SERVICE);
vibe.vibrate(100);
mDBHelper = new DatabaseHelper(context);
mDb = mDBHelper.getWritableDatabase();
ContentValues contentValues=new ContentValues();
contentValues.put("verseid",colors.get(position));
final long check=mDb.insert("highlight",null,contentValues);
//id get
//postion
//Toast.makeText(activity, ""+getItemId(position), Toast.LENGTH_SHORT).show();
ColorPicker colorPicker = new ColorPicker(context);
colorPicker.setColors(colors).setColumns(4).setTitle("HIGHLIGHT VERSE").setRoundColorButton(true).setOnChooseColorListener(new ColorPicker.OnChooseColorListener() {
@Override
public void onChooseColor(int position, int color) {
linearLayout.setBackgroundColor(Color.parseColor(colors.get(position)));
}
@Override
public void onCancel() {
}
}).show();
return false;
}
});
*/
return view;
}
public boolean Checkisfavourite(String TableName, String dbfield, String fieldValue) {
mDBHelper = new DatabaseHelper(context);
mDb = mDBHelper.getReadableDatabase();
String Query = "Select * from " + TableName + " where " + dbfield + " = " + fieldValue;
Cursor cursor = mDb.rawQuery(Query, null);
if(cursor.getCount() <= 0){
cursor.close();
// Toast.makeText(activity, "false", Toast.LENGTH_SHORT).show();
return false;
}else {
// Toast.makeText(activity, "TRUE", Toast.LENGTH_SHORT).show();
}
cursor.close();
return true;
}
public boolean colorcheck(String TableName, String dbfield, String fieldValue) {
mDBHelper = new DatabaseHelper(context);
mDb = mDBHelper.getReadableDatabase();
String Query = "Select * from " + TableName + " where " + dbfield + " = " + fieldValue;
Cursor cursor = mDb.rawQuery(Query, null);
if(cursor.getCount() <= 0){
cursor.close();
// Toast.makeText(activity, "false", Toast.LENGTH_SHORT).show();
return false;
}else {
// Toast.makeText(activity, "TRUE", Toast.LENGTH_SHORT).show();
}
cursor.close();
return true;
}
@Override
public void onInit(int status) {
if (status == TextToSpeech.SUCCESS) {
int result = textToSpeech.setLanguage(Locale.US);
// tts.setPitch(5); // set pitch level
// tts.setSpeechRate(2); // set speech speed rate
if (result == TextToSpeech.LANG_MISSING_DATA
|| result == TextToSpeech.LANG_NOT_SUPPORTED) {
Log.e("TTS", "Language is not supported");
} else {
}
} else {
Log.e("TTS", "Initilization Failed");
}
}
private void singleverse(String text) {
DefaultSettings.speed(context);
textToSpeech.setPitch(DefaultSettings.pitchvalue);
textToSpeech.setSpeechRate(DefaultSettings.speedvalue);
textToSpeech.speak(text, TextToSpeech.QUEUE_FLUSH, null);
}
public void stop(){
if (textToSpeech != null) {
textToSpeech.stop();
textToSpeech.shutdown();
}
}
}
主要问题是您的 TextToSpeech 对象属于您的 BaseAdapter，而它应该属于父活动。
我不会将其存放在适配器中并在每次用户单击项目时调用 speak ，而是将其存放在父活动中，并使用"接口回调"，当用户单击项目时向父项发送消息，发送回字符串进行语音。 此回调关系的工作方式与您已在使用的 TextToSpeech.OnInitListener 回调完全相同。
TTS 属于父活动后，您可以像往常一样使用活动生命周期函数来控制 TTS 的关闭。
如果您学习并理解以下内容，您应该能够将其合并到您的代码中并获得有效的解决方案：
对自定义基本适配器进行以下更改：
// Remove the TextToSpeech object from this class.
public class MyBaseAdapter {
// add this interface definition to your adapter
public interface SpeechClickSubscriber {
void stringNeedsToBeSpoken(String verse);
}
// add this property (the subscriber)
private SpeechClickSubscriber speechClickSubscriber;
// *add* this functionality to your adapter's existing constructor
MyBaseAdapter(SpeechClickSubscriber parent) {
speechClickSubscriber = parent;
}
//...
// change this section of code in your getView() method
speakverse.setOnClickListener(new View.OnClickListener()
{
@Override
public void onClick (View v){
// change this...
// singleverse(verselist.get(position).toString());
// to this:
speechClickSubscriber.stringNeedsToBeSpoken(verselist.get(position).toString());
}
});
// ...
}
对您的主活动(或任何父活动(进行以下更改：
// add the SpeechClickSubscriber implementation
public class MainActivity extends AppCompatActivity implements MyBaseAdapter.SpeechClickSubscriber, TextToSpeech.OnInitListener {
MyBaseAdapter adapter;
TextToSpeech textToSpeech;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
// using app context is better and less error prone.
textToSpeech = new TextToSpeech(getApplicationContext(), this);
}
// *add* this method to this activity (this is the answer to your question)
@Override
protected void onStop() {
super.onStop();
stopTTS();
}
// use this method as your "onStart()" method...
// this will help prevent any user input processing until the tts is initialized.
private void start_Activity_Because_TTS_Has_Initialized() {
adapter = new MyBaseAdapter(this);
}
// *MOVE* this method from your base adapter to this (parent) activity:
@Override
public void onInit(int status) {
if (status == TextToSpeech.SUCCESS) {
int result = textToSpeech.setLanguage(Locale.US);
// tts.setPitch(5); // set pitch level
// tts.setSpeechRate(2); // set speech speed rate
if (result == TextToSpeech.LANG_MISSING_DATA
|| result == TextToSpeech.LANG_NOT_SUPPORTED) {
Log.e("TTS", "Language is not supported");
} else {
}
} else {
Log.e("TTS", "Initilization Failed");
}
}
// *move* and *rename* this method from your adapter to the parent activity:
// from:
/*
private void singleverse(String text) {
DefaultSettings.speed(context);
textToSpeech.setPitch(DefaultSettings.pitchvalue);
textToSpeech.setSpeechRate(DefaultSettings.speedvalue);
textToSpeech.speak(text, TextToSpeech.QUEUE_FLUSH, null);
} */
// to:
@Override
public void stringNeedsToBeSpoken(String verse) {
Log.i("XXX","stringNeedsToBeSpoken() was called because the user clicked an item.");
Log.i("XXX","This method is being called because this activity subscribes to the callback we created and added to our base adapter.");
//DefaultSettings.speed(context); // <----------------- I don't know what this does.
// I'm assuming that DefaultSettings is a static class you have made.
textToSpeech.setPitch(DefaultSettings.pitchvalue);
textToSpeech.setSpeechRate(DefaultSettings.speedvalue);
textToSpeech.speak(verse, TextToSpeech.QUEUE_FLUSH, null);
}
public void stopTTS(){
if (textToSpeech != null) {
textToSpeech.stop();
textToSpeech.shutdown();
}
}
}