的Android SDK的推出懸掛裝置

Question

嗨，我是初學者，我想寫上單擊事件簡單，所以我拿出這些代碼的Android SDK和Eclipse：

package com.example.aplic; 

import android.support.v7.app.ActionBarActivity; 
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.View.OnClickListener; 
import android.view.ViewGroup; 
import android.widget.Button; 
import android.widget.TextView; 

public class MainActivity extends ActionBarActivity { 

    @Override 
    protected void onCreate(Bundle savedInstanceState) { 
     super.onCreate(savedInstanceState); 
     setContentView(R.layout.activity_main); 

     Button b = (Button) findViewById(R.id.button1); 

     b.setOnClickListener(new OnClickListener() { 
      @Override 
      public void onClick(View v) { 
       TextView tx = (TextView) findViewById(R.id.textView1); 
       tx.setText("yourtext"); 
      } 
     }); 

     if (savedInstanceState == null) { 
      getSupportFragmentManager().beginTransaction() 
        .add(R.id.container, new PlaceholderFragment()) 
        .commit(); 
     } 

    } 


    @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; 
     } 
    } 

} 

和：

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android" 
    xmlns:tools="http://schemas.android.com/tools" 
    android:layout_width="match_parent" 
    android:layout_height="match_parent" 
    android:paddingBottom="@dimen/activity_vertical_margin" 
    android:paddingLeft="@dimen/activity_horizontal_margin" 
    android:paddingRight="@dimen/activity_horizontal_margin" 
    android:paddingTop="@dimen/activity_vertical_margin" 
    tools:context="com.example.aplic.MainActivity$PlaceholderFragment" > 

    <TextView 
     android:id="@+id/textView1" 
     android:layout_width="wrap_content" 
     android:layout_height="wrap_content" 
     android:text="@string/hello_world" /> 

    <Button 
     android:id="@+id/button1" 
     android:layout_width="wrap_content" 
     android:layout_height="wrap_content" 
     android:layout_below="@+id/textView1" 
     android:layout_marginTop="110dp" 
     android:layout_toRightOf="@+id/textView1" /> 

    <ImageView 
     android:id="@+id/imageView1" 
     android:layout_width="wrap_content" 
     android:layout_height="wrap_content" 
     android:layout_alignLeft="@+id/button1" 
     android:layout_below="@+id/button1" 
     android:layout_marginTop="96dp" 
     android:contentDescription="@string/abc_action_mode_done" 
     android:src="@drawable/abc_ab_bottom_solid_dark_holo" /> 

</RelativeLayout> 

問題是，當我在仿真器上啓動代碼時，它掛起並重置，當我在真實設備中啓動它時，它關閉程序，我不知道它有什麼問題，是否使用錯誤事件？

PS：當我刪除onclick事件部分，它工作正常，但它不會對點擊作出反應。

activity_main.xml中：

<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.deomanapp.MainActivity" 
    tools:ignore="MergeRootFrame" /> 

Answer 1

它看起來像按鈕所屬fragment_main.xml。

從您的評論

名稱是fragment_main.xml

它不掛。它的崩潰。您可能獲得NullPointerException。

更改爲

@Override 
    public View onCreateView(LayoutInflater inflater, ViewGroup container, 
      Bundle savedInstanceState) { 
     final View rootView = inflater.inflate(R.layout.fragment_main, container, false); 
     Button b = (Button) rootView.findViewById(R.id.button1); 

     b.setOnClickListener(new OnClickListener() { 
     @Override 
     public void onClick(View v) { 
      TextView tx = (TextView) rootview.findViewById(R.id.textView1); 
      tx.setText("yourtext"); 
     } 
    }); 
     return rootView; 
    }