android apk mHandler2
16lz
2021-01-25
package com.example.helloworld;import android.support.v7.app.ActionBarActivity;import android.support.v4.app.Fragment;import android.os.Bundle;import android.os.Message;import android.view.LayoutInflater;import android.view.Menu;import android.view.MenuItem;import android.view.View;import android.view.ViewGroup;import android.widget.Toast;import android.os.Handler;public class MainActivity extends ActionBarActivity { @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); Message msg2 = new Message(); msg2.what = 1; mHandler2.sendMessage(msg2); if (savedInstanceState == null) { getSupportFragmentManager().beginTransaction() .add(R.id.container, new PlaceholderFragment()) .commit(); } } private Handler mHandler2 = new Handler(){ public void handleMessage(Message msg){ int what = msg.what; boolean down = (what==1?true:false); Toast toast=Toast.makeText(getApplicationContext(), "今天天气很好"+down, Toast.LENGTH_SHORT); toast.show(); } }; @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; } }}