Android Toast效果

package org.elvalad.activitytest;

import android.app.Activity;
import android.os.Bundle;
import android.view.View;
import android.view.Window;
import android.widget.Button;
import android.widget.Toast;

/**
 * Created by elvalad on 2015/3/26.
 */
public class FirstActivity extends Activity {
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        /* 隐藏标题栏 */
        requestWindowFeature(Window.FEATURE_NO_TITLE);
        setContentView(R.layout.first_layout);

        /* 在Activity中使用Toast */
        Button button1 = (Button) findViewById(R.id.button_1);
        button1.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                Toast.makeText(FirstActivity.this, "you click button 1",
                        Toast.LENGTH_SHORT).show();
            }
        });
    }
}

<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="org.elvalad.activitytest">

    <application android:allowBackup="true" android:label="@string/app_name"
        android:icon="@mipmap/ic_launcher" android:theme="@style/AppTheme">

        <activity android:name=".FirstActivity"
            android:label="This is first activity" >
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />
                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
    </application>

</manifest>

<?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">

    <Button
        android:id="@+id/button_1"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="Button1" />
</LinearLayout>