我观看和学习的youtube视频位于以下链接:-
Title is How to make an android app NO PROGRAMMING SKILLS NEEDED pt 1,2,3
1.http://www.youtube.com/watch?v=Be-YnLcPEdA , http://www.youtube.com/watch?v=Rt0wX3I1Wrg , http://www.youtube.com/watch?v=mkhRCWfTD4A.
我是一名三年级的文凭学生。我之前没有任何编程和应用程序创建方面的知识。我需要为我最后一年的项目开发应用程序。有人请帮帮我。我已经下载了android sdk捆绑包,并试图按照youtube视频完成所有操作。
我有3条错误消息,如下所示。:-
syntax error on token"(";expected.MainActivity.java .line28.type:java problem
syntax error on token")";expected.MainActivity.java .line28.type:java problem
Void is an invalid type for the variableCalculate.MainActivity.java.line28.type:java problem
main activity.java的代码如下:-
import android.support.v7.app.ActionBarActivity;
import android.support.v7.app.ActionBar;
import android.support.v4.app.Fragment;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.view.ViewGroup;
import android.widget.EditText;
import android.widget.TextView;
import android.os.Build;
public class MainActivity extends ActionBarActivity {
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
if (savedInstanceState == null) {
getSupportFragmentManager().beginTransaction()
.add(R.id.container, new PlaceholderFragment())
.commit();
} {
public void Calculate( View v) {
EditText num1text=(EditText)findViewById(R.id.num1text);
EditText num2text=(EditText)findViewById(R.id.num2text);
Integer num1=Integer.parseInt(num1text.getText().toString()) ,num2=Integer.parseInt(num2text.getText().toString());
Integer ans=num1+num2;
TextView answer =(TextView)findViewById(R.id.answertxt);
answer.setText("answer :"+ans.toString());
}
}
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.main, menu);
return true;
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle action bar item clicks here. The action bar will
// automatically handle clicks on the Home/Up button, so long
// as you specify a parent activity in AndroidManifest.xml.
int id = item.getItemId();
if (id == R.id.action_settings) {
return true;
}
return super.onOptionsItemSelected(item);
}
/**
* A placeholder fragment containing a simple view.
*/
public static class PlaceholderFragment extends Fragment {
public PlaceholderFragment() {
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View rootView = inflater.inflate(R.layout.fragment_main, container, false);
return rootView;
}
}
}
Fragment main.xml的代码如下:-
<LinearLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_alignParentTop="true"
android:layout_centerHorizontal="true"
android:orientation="vertical" >
<TextView
android:id="@+id/num1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="@string/num1" />
<EditText
android:id="@+id/num1text"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:ems="10"
android:inputType="numberDecimal" />
<TextView
android:id="@+id/num2"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="@string/num2" />
<EditText
android:id="@+id/num2text"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:ems="10"
android:inputType="numberDecimal" />
<Button
android:id="@+id/button1"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="@string/calc"
android:onClick="Calculate" />
<TextView
android:id="@+id/answertxt"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="@string/ans" />
</LinearLayout>
codes for activity_main.xml as below:-
<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:id="@+id/container"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context="com.example.test.MainActivity"
tools:ignore="MergeRootFrame" />
我需要学习如何制作应用程序,因为我需要为我的项目做。在真实的项目中,智能手机Android KITKAT应该能够使用来自RFduino的蓝牙低能耗(BLE(和来自RFdui诺的BLE中的广告功能接收数据,并将数据发送回RFduino以完成一些任务。我的电子邮件地址是yokesmohan@gmail.com,s10135557@connect.np.edu.sg.Someone请帮帮我。
if (savedInstanceState == null) {
getSupportFragmentManager().beginTransaction()
.add(R.id.container, new PlaceholderFragment())
.commit();
} {
在上面的行中,有一个额外的开放大括号({
(。尝试删除它。