常见控件的使用方法 TextView EditText Button Menu

这篇文章将给大家介绍TextView EditText Button Menu这几个控件的使用方法，同时在布局文件里面还有一个新的东西，线性布局，以及string.xml的使用，这里的string.xml是用来做国际化用的。

1、创建第一个Activity,ThridLessonDemo1.java

package com.example.helloworld;

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 ThridLessonDemo1 extends Activity {
private EditText num1;
private EditText num2;
private TextView myTextView;
private Button calculate;

@Override
protected void onCreate(Bundle savedInstanceState) {
// TODO Auto-generated method stub
super.onCreate(savedInstanceState);
// 根据控件的ID来取得代表控件的对象
setContentView(R.layout.thridfirst);
num1 = (EditText) findViewById(R.id.Numo);
num2 = (EditText) findViewById(R.id.Numt);
myTextView = (TextView) findViewById(R.id.myTextView);
calculate = (Button) findViewById(R.id.calculate);
myTextView.setText(R.string.cy);
calculate.setText(R.string.js);
calculate.setOnClickListener(new myButtonListener());
}

class myButtonListener implements OnClickListener {

public void onClick(View arg0) {
// TODO Auto-generated method stub
String v1 = num1.getText().toString();
String v2 = num2.getText().toString();
Intent intent = new Intent();
intent.putExtra("num1", v1);
intent.putExtra("num2", v2);
intent.setClass(ThridLessonDemo1.this, ThridLessonDemo2.class);
startActivity(intent);
}

}
//当客户点击MENU按钮时调用该方法
@Override
public boolean onCreateOptionsMenu(Menu menu) {

menu.add(0, 1, 1, R.string.ext);
menu.add(0, 2, 2, R.string.about);

// TODO Auto-generated method stub
return super.onCreateOptionsMenu(menu);
}
//当客户点击菜单当中的某一个选项时，会调用该方法
@Override
public boolean onOptionsItemSelected(MenuItem item) {
if (item.getItemId() == 1) {
finish();
}

// TODO Auto-generated method stub
return super.onOptionsItemSelected(item);
}

}

2、创建第二个Activity,ThridLessonDemo2.java

package com.example.helloworld;

import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.widget.TextView;

public class ThridLessonDemo2 extends Activity {

private TextView resultView;

@Override
protected void onCreate(Bundle savedInstanceState) {
// TODO Auto-generated method stub
super.onCreate(savedInstanceState);
setContentView(R.layout.thridsecond);
resultView = (TextView) findViewById(R.id.resultView);
Intent intent = getIntent();
String num1 = intent.getStringExtra("num1");
String num2 = intent.getStringExtra("num2");
int _num1 = Integer.parseInt(num1);
int _num2 = Integer.parseInt(num2);
int result = _num1 * _num2;
resultView.setText(result + "");
}

}

3、创建第一个Activity的布局文件，thridfirst.xml

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical" >

<EditText
android:id="@+id/Numo"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:inputType="number" />

<TextView
android:id="@+id/myTextView"
android:layout_width="fill_parent"
android:layout_height="wrap_content" />

<EditText
android:id="@+id/Numt"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:inputType="number" />

<Button
android:id="@+id/calculate"
android:layout_width="fill_parent"
android:layout_height="wrap_content" />

</LinearLayout>

4、创建第二个Activity的布局文件，thridsecond.xml

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical" >

<TextView
android:id="@+id/resultView"
android:layout_width="fill_parent"
android:layout_height="wrap_content" />

</LinearLayout>

5、修改res/values/strings.xml

<resources>

<string name="app_name">HelloWorld</string>
<string name="hello_world">Hello world!</string>
<string name="menu_settings">Settings</string>
<string name="title_activity_main">MainActivity</string>
<string name="other">otherActivity</string>
<string name="ok">确定</string>
<string name="cy">乘以</string>
<string name="js">计算</string>
<string name="ext">退出</string>
<string name="about">关于</string>
</resources>

6、注册这两个Activity

<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.example.helloworld"
android:versionCode="1"
android:versionName="1.0" >

<uses-sdk
android:minSdkVersion="4"
android:targetSdkVersion="15" />

<application
android:icon="@drawable/ic_launcher"
android:label="@string/app_name"
android:theme="@style/AppTheme" >
<activity
android:name=".MainActivity"
android:label="@string/title_activity_main" >
</activity>
<activity
android:name=".SecondLessonDemo1"
android:label="@string/other" >
</activity>
<activity
android:name=".SecondLessonDemo2"
android:label="dd" >
</activity>
<activity
android:name=".ThridLessonDemo1"
android:label="dd2" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />

<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<activity
android:name=".ThridLessonDemo2"
android:label="dd3" >
</activity>
</application>

</manifest>