Question

求解，关于安卓开发出现Unfortunately，activity has stopped问题

package com.example.layout01;
import android.support.v7.app.ActionBarActivity;import android.support.v4.app.Fragment;import android.content.Intent;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;
public class MainActivity extends ActionBarActivity { private Button myButton = null; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); myButton = (Button)findViewById(R.id.myButton); myButton.setOnClickListener(new MyButtonListener()); 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; } } class MyButtonListener implements OnClickListener{
@Override public void onClick(View v) { // TODO Auto-generated method stub //生成一个Intent对象 Intent intent = new Intent(); intent.setClass(MainActivity.this,OtherActivity.class); MainActivity.this.startActivity(intent); } }}
这是其中一个java代码，希望各位大神帮忙，谢谢！
这个是LogCat提示的

Answer 1

看log是你的MainActivity.java的24行有空指针。代码中是getSupportFragmentManager()返回的是null导致的， 重点查这个函数吧。