android吐司选择课程,步步为营_Android开发课[32]_用户界面之Toast（吐司）

主题：用户界面之Toast(吐司)

-常用于APP中的一些小提示

Toast的结构分析：

Toast toast=Toast.makeText(MainActivity.this, “默认的Toast”, Toast.LENGTH_SHORT).show();

第一个参数：当前的上下文环境。可用getApplicationContext()或this .

第二个参数：要显示的字符串。也可是R.string中字符串ID

第三个参数：显示的时间长短。Toast默认的有两个LENGTH_LONG(长)和LENGTH_SHORT(短)，也可以使用毫秒如2000ms

最后显示toast信息 ：调用show()方法 。

Toast(实例)：

默认Toast效果：

自定义显示位置Toast效果：

自定义带图片Toast效果：

完全自定义Toast效果：

线程启动Toast效果：

实现代码：

activity_main.xml:

android:orientation="vertical"

android:layout_width="fill_parent"

android:layout_height="fill_parent"

android:padding="5dip"

android:gravity="center">

android:layout_height="wrap_content"

android:layout_width="fill_parent"

android:id="@+id/btnSimpleToast"

android:text="默认">

android:layout_height="wrap_content"

android:layout_width="fill_parent"

android:text="自定义显示位置"

android:id="@+id/btnSimpleToastWithCustomPosition">

android:layout_height="wrap_content"

android:layout_width="fill_parent"

android:id="@+id/btnSimpleToastWithImage"

android:text="带图片">

android:layout_height="wrap_content"

android:layout_width="fill_parent"

android:text="完全自定义"

android:id="@+id/btnCustomToast">

android:layout_height="wrap_content"

android:layout_width="fill_parent"

android:text="其他线程"

android:id="@+id/btnRunToastFromOtherThread">

custom.xml:

android:layout_height="wrap_content" android:layout_width="wrap_content"

android:background="#ffffffff" android:orientation="vertical"

android:id="@+id/llToast" >

android:layout_margin="1dip"

android:textColor="#ffffffff"

android:layout_width="fill_parent"

android:gravity="center"

android:background="#bb000000"

android:id="@+id/tvTitleToast" />

android:orientation="vertical"

android:id="@+id/llToastContent"

android:layout_marginLeft="1dip"

android:layout_marginRight="1dip"

android:layout_marginBottom="1dip"

android:layout_width="wrap_content"

android:padding="15dip"

android:background="#44000000" >

android:layout_gravity="center"

android:layout_width="wrap_content"

android:id="@+id/tvImageToast" />

android:paddingRight="10dip"

android:paddingLeft="10dip"

android:layout_width="wrap_content"

android:gravity="center"

android:textColor="#ff000000"

android:id="@+id/tvTextToast" />

MainActivity.java:

import android.app.Activity;

import android.os.Bundle;

import android.os.Handler;

import android.view.Gravity;

import android.view.LayoutInflater;

import android.view.View;

import android.view.View.OnClickListener;

import android.view.ViewGroup;

import android.widget.ImageView;

import android.widget.LinearLayout;

import android.widget.TextView;

import android.widget.Toast;

public class MainActivity extends Activity implements OnClickListener {

Handler handler = new Handler();

@Override

public void onCreate(Bundle savedInstanceState) {

super.onCreate(savedInstanceState);

setContentView(R.layout.activity_main);

findViewById(R.id.btnSimpleToast).setOnClickListener(this);

findViewById(R.id.btnSimpleToastWithCustomPosition).setOnClickListener(this);

findViewById(R.id.btnSimpleToastWithImage).setOnClickListener(this);

findViewById(R.id.btnCustomToast).setOnClickListener(this);

findViewById(R.id.btnRunToastFromOtherThread).setOnClickListener(this);

}

public void showToast() {

handler.post(new Runnable() {

@Override

public void run() {

Toast.makeText(getApplicationContext(), "我来自其他线程！",

Toast.LENGTH_SHORT).show();

}

});

}

@Override

public void onClick(View v) {

Toast toast = null;

switch (v.getId()) {

case R.id.btnSimpleToast:

Toast.makeText(getApplicationContext(), "默认Toast样式",

Toast.LENGTH_SHORT).show();

break;

case R.id.btnSimpleToastWithCustomPosition:

toast = Toast.makeText(getApplicationContext(),"自定义位置Toast", Toast.LENGTH_LONG);

toast.setGravity(Gravity.CENTER, 0, 0);

toast.show();

break;

case R.id.btnSimpleToastWithImage:

toast = Toast.makeText(getApplicationContext(),"带图片的Toast", Toast.LENGTH_LONG);

toast.setGravity(Gravity.CENTER, 0, 0);

LinearLayout toastView = (LinearLayout) toast.getView();

ImageView imageCodeProject = new ImageView(getApplicationContext());

imageCodeProject.setImageResource(R.drawable.myimage);

toastView.addView(imageCodeProject, 0);

toast.show();

break;

case R.id.btnCustomToast:

LayoutInflater inflater = getLayoutInflater();

View layout = inflater.inflate(R.layout.custom, (ViewGroup) findViewById(R.id.llToast));

ImageView image = (ImageView) layout.findViewById(R.id.tvImageToast);

image.setImageResource(R.drawable.myimage);

TextView title = (TextView) layout.findViewById(R.id.tvTitleToast);

title.setText("Attention");

TextView text = (TextView) layout.findViewById(R.id.tvTextToast);

text.setText("完全自定义Toast");

toast = new Toast(getApplicationContext());

toast.setGravity(Gravity.CENTER, 0, 0);

toast.setDuration(Toast.LENGTH_LONG);

toast.setView(layout);

toast.show();

break;

case R.id.btnRunToastFromOtherThread:

new Thread(new Runnable() {

public void run() {

showToast();

}

}).start();

break;

}

}

}