Activity介绍

1.Activity使用方法(跳转):

(1)写Activity类继承Activity

package com.example.test2;

import android.app.Activity;
import android.os.Bundle;
import android.util.Log;
import android.view.Menu;
import android.widget.Button;
import android.widget.CheckBox;
import android.widget.CompoundButton;
import android.widget.RadioGroup;
import android.widget.RadioGroup.OnCheckedChangeListener;

public class SecondActivity extends Activity {

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

}

 (2)写布局文件

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical" >

    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="this is second activity"
        />

</LinearLayout>

(3) AndroidManifest.xml注册Activity

(4)MainActivity中通过一个按钮的点击事件引出第二个Activity

全部代码:

package com.example.test2;

import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.util.Log;
import android.view.Menu;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.CheckBox;
import android.widget.RadioGroup;
import android.widget.RadioGroup.OnCheckedChangeListener;

public class MainActivity extends Activity implements OnCheckedChangeListener {

    private Button login_button;
    private Button reset;
    private RadioGroup rg;
    private Button other;
    private CheckBox checkBox1;
    private Button myButton;

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

        rg = (RadioGroup) this.findViewById(R.id.radioGroup1);
        rg.setOnCheckedChangeListener(this);

        Button btn  = (Button) findViewById(R.id.button1);
        btn.setOnClickListener(new OnClickListener() {

            @Override
            public void onClick(View arg0) {
                // TODO Auto-generated method stub
                Intent intent = new Intent(MainActivity.this,SecondActivity.class);
                MainActivity.this.startActivity(intent);
            }
        });

    }

    @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 void onCheckedChanged(RadioGroup arg0, int checkId) {
        // TODO Auto-generated method stub
        switch(checkId){
        case R.id.radio0:
            Log.i("tag", "当前选中男");
            break ;
        case R.id.radio1:
            Log.i("tag", "当前选中女");
            break ;
        default:
            break ;
        }
    }

}

 (5)效果: