09_消息通知Toast和Notification

1. Toast

　　学习创建长短不一的Toast提示，并自定义Toast在屏幕上的位置以及Toast的外观。

package com.example.toastdemo;

import android.app.Activity;
import android.app.ActionBar;
import android.app.Fragment;
import android.os.Bundle;
import android.view.Gravity;
import android.view.LayoutInflater;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.view.ViewGroup;
import android.widget.Button;
import android.widget.ImageView;
import android.widget.Toast;
import android.os.Build;

public class MainActivity extends Activity {

    private Button btnShowToastShort, btnShowToastLong, btnShowToastImage;

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

        btnShowToastShort = (Button) findViewById(R.id.btnShowToast);
        btnShowToastLong = (Button) findViewById(R.id.btnShowToastLong);
        btnShowToastImage = (Button) findViewById(R.id.btnShowToastImage);

        btnShowToastShort.setOnClickListener(new View.OnClickListener() {

            @Override
            public void onClick(View v) {
                // 可以改变Toast显示的位置；

                Toast shortToast = Toast.makeText(MainActivity.this,
                        "显示一个简短的Toast", Toast.LENGTH_SHORT);
                shortToast.setGravity(Gravity.CENTER, 0, 0);
                shortToast.show();
            }
        });

        btnShowToastLong.setOnClickListener(new View.OnClickListener() {

            @Override
            public void onClick(View v) {
                Toast.makeText(MainActivity.this, "显示一个较长的Toast",
                        Toast.LENGTH_LONG).show();
            }
        });

        btnShowToastImage.setOnClickListener(new View.OnClickListener() {

            // 显示图片之后，就不会显示文字。
            // 若想显示其它，需要定义Layout
            @Override
            public void onClick(View v) {
                Toast imageToast = Toast.makeText(MainActivity.this,
                        "显示一个图片的Toast", Toast.LENGTH_LONG);
                ImageView imageView = new ImageView(MainActivity.this);
                imageView.setImageResource(R.drawable.ic_launcher);
                imageToast.setView(imageView);
                imageToast.show();
            }
        });

    }

}

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:id="@+id/container"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical"
    tools:context="com.example.toastdemo.MainActivity"
    tools:ignore="MergeRootFrame" >

    <Button
        android:id="@+id/btnShowToast"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:text="显示一个简短的Toast" />

    <Button
        android:id="@+id/btnShowToastLong"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:text="显示一个较长的Toast" />

    <Button
        android:id="@+id/btnShowToastImage"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:text="显示一个图片的Toast" />

</LinearLayout>

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.example.toastdemo"
    android:versionCode="1"
    android:versionName="1.0" >

    <uses-sdk
        android:minSdkVersion="14"
        android:targetSdkVersion="19" />

    <application
        android:allowBackup="true"
        android:icon="@drawable/ic_launcher"
        android:label="@string/app_name"
        android:theme="@style/AppTheme" >
        <activity
            android:name="com.example.toastdemo.MainActivity"
            android:label="@string/app_name" >
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

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

</manifest>

2. Notification

　　学习创建Notification对象，为其指定标题、内容和图标，以及Notification的更新方法。

package com.example.notificationdemo;

import android.app.Activity;
import android.app.Notification;
import android.app.NotificationManager;
import android.content.Context;
import android.os.Bundle;
import android.support.v4.app.NotificationCompat;
import android.support.v4.app.NotificationCompat.Builder;
import android.view.View;
import android.widget.Button;

public class MainActivity extends Activity {

    public static final int NOTIFICATION_ID = 1234;
    private Button btn1;
    private int conter = 0;

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

        btn1 = (Button) findViewById(R.id.but1);
        btn1.setOnClickListener(new View.OnClickListener() {

            @Override
            public void onClick(View v) {
                conter++;
                Builder builder = new NotificationCompat.Builder(
                        MainActivity.this);
                builder.setSmallIcon(R.drawable.ic_launcher);
                builder.setContentTitle("你已经创建" + conter + "个新消息了！");
                builder.setContentText("Notification~~~");

                Notification notification = builder.build();
                NotificationManager manager = (NotificationManager) getSystemService(Context.NOTIFICATION_SERVICE);
                manager.notify(NOTIFICATION_ID, notification);

            }
        });

    }

}

<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:id="@+id/container"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context="com.example.notificationdemo.MainActivity"
    tools:ignore="MergeRootFrame" >

    <Button
        android:id="@+id/but1"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:text="创建一个提示" />

</FrameLayout>

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.example.notificationdemo"
    android:versionCode="1"
    android:versionName="1.0" >

    <uses-sdk
        android:minSdkVersion="14"
        android:targetSdkVersion="19" />

    <application
        android:allowBackup="true"
        android:icon="@drawable/ic_launcher"
        android:label="@string/app_name"
        android:theme="@style/AppTheme" >
        <activity
            android:name="com.example.notificationdemo.MainActivity"
            android:label="@string/app_name" >
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

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

</manifest>