android Intent和菜单的使用

首先我们需要知道Intent这个东西是用来干什么的：

   intent主要可以看着是一个能够在两个Activity之间传输数据的这么一个对象，那么他的具体用法怎么用啊

我们下来就来看看这个例子吧：

package demo.jsj;

import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;

public class Activity03 extends Activity {
    private EditText factorOne;
    private EditText factorTwo;
    private TextView symbol;
    private Button calculate;
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        //根据控件的Id取得控件的对象(通过布局文件进行获取)
        factorOne = (EditText)this.findViewById(R.id.factorOne);
        factorTwo = (EditText)this.findViewById(R.id.factorTwo);
        symbol = (TextView)this.findViewById(R.id.symbol);
        calculate = (Button)findViewById(R.id.calculate);
        symbol.setText(R.string.symbol);
        calculate.setText(R.string.caloulate);
        calculate.setOnClickListener(new ClaculateListener());
    }
    
    //添加菜单
    
    
    @Override
	public boolean onCreateOptionsMenu(Menu menu) {
		// TODO Auto-generated method stub
    	menu.add(0,1,1,R.string.out);//第二个参数为ID
    	menu.add(0,2,2,R.string.about);
		return super.onCreateOptionsMenu(menu);
	}
    //设置菜单的操作
	@Override
	public boolean onOptionsItemSelected(MenuItem item) {
		if(item.getItemId() == 1){
			finish();
		}
		return super.onOptionsItemSelected(item);
	}

	class ClaculateListener implements OnClickListener{

		@Override
		public void onClick(View v) {
			//取得两个控件的值
			String factorOneStr = factorOne.getText().toString();
			String factorTwoStr = factorTwo.getText().toString();
			Intent intent = new Intent();
			intent.putExtra("one", factorOneStr);
			intent.putExtra("two", factorTwoStr);
			intent.setClass(Activity03.this, ResultActivity.class);
			Activity03.this.startActivity(intent);
		}
    	
    }
}

 

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    >
    
<EditText
	android:id="@+id/factorOne"
	android:layout_width="fill_parent"
	android:layout_height="wrap_content"
	/>
<TextView  
	android:id="@+id/symbol"
    android:layout_width="fill_parent" 
    android:layout_height="wrap_content" 
    android:text="@string/hello"
    />
<EditText
	android:id="@+id/factorTwo"
	android:layout_width="fill_parent"
	android:layout_height="wrap_content"
	/>
<Button
	android:id="@+id/calculate"
	android:layout_width="fill_parent"
	android:layout_height="wrap_content"
	/>
</LinearLayout>