实验2 Activity和Intent-任务1

一、运行效果图

二、核心代码

<pre class="java" name="code"><?xml version="1.0" encoding="utf-8"?><RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"    android:layout_width="match_parent"    android:layout_height="match_parent"    android:background="@drawable/bg"    android:paddingBottom="@dimen/activity_vertical_margin"    android:paddingLeft="@dimen/activity_vertical_margin"    android:paddingRight="@dimen/activity_horizontal_margin"    android:paddingTop="@dimen/activity_vertical_margin" >    <EditText        android:id="@+id/etName"        android:layout_width="wrap_content"        android:layout_height="wrap_content"        android:layout_alignParentRight="true"        android:layout_alignParentTop="true"        android:layout_marginRight="32dp"        android:layout_marginTop="94dp"        android:background="@android:drawable/edit_text"        android:drawableLeft="@drawable/name"        android:ems="10"        android:hint="@string/etNamePrompt"        android:textColorHint="#191970" >        <requestFocus />    </EditText>    <Button        android:id="@+id/btnClick"        android:layout_width="wrap_content"        android:layout_height="wrap_content"        android:layout_below="@+id/etName"        android:layout_centerHorizontal="true"        android:layout_marginTop="26dp"        android:background="@drawable/handok" >    </Button></RelativeLayout>

<p>package cn.edu.bzu.helloandroid;</p><p>import android.annotation.SuppressLint;import android.app.Activity;import android.os.Bundle;import android.view.View;import android.view.View.OnClickListener;import android.widget.Button;import android.widget.EditText;import android.widget.ImageView;import android.widget.LinearLayout;import android.widget.Toast;

public class MainActivity extends Activity { public static final int Gravity = 0; private Button btnClick; private EditText etName; 

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

  btnClick = (Button) findViewById(R.id.btnClick);  btnClick.setOnClickListener(new ClickHandler());

  etName = (EditText) findViewById(R.id.etName);

}

 class ClickHandler implements OnClickListener {

 private static final int CENTER = 0;

 @SuppressLint("ShowToast")  @Override  public void onClick(View view) {   String name = etName.getText().toString();   Toast toast = Toast.makeText(MainActivity.this, "你好！ " + name,     Toast.LENGTH_SHORT);      /*    * Toast toast = Toast.makeText(getApplicationContext(),    * name,Toast.LENGTH_LONG);    */   // LinearLayout toast_layout = (LinearLayout) toast.getView();   toast.setGravity(Gravity, CENTER, 130);// 创建图片视图对象   ImageView imageView = new ImageView(getApplicationContext());// 设置图片   imageView.setImageResource(R.drawable.smile_blak);// 获得toast的布局   LinearLayout toastView = (LinearLayout) toast.getView();// 设置此布局为横向的   toastView.setOrientation(LinearLayout.HORIZONTAL);// 将ImageView在加入到此布局中的第一个位置   toastView.addView(imageView, 0);   toast.show();

 /*    * Toast toast=Toast.makeText(getApplicationContext(), 0, 0);    * toast.setGravity(Gravity,BIND_ABOVE_CLIENT,50); LinearLayout    * layout=(LinearLayout) toast.getView(); ImageView image=new    * ImageView(getApplicationContext());    * image.setImageResource(R.drawable.smile_blak);    * layout.addView(image,0); toast.show();   * public void showToast(Context context, String ) { Toast toast =   * Toast.makeText(context, , Toast.LENGTH_SHORT);   * toast.setGravity(Gravity, BIND_ABOVE_CLIENT, 0); LinearLayout layout   * = (LinearLayout) toast.getView(); ImageView image = new   * ImageView(context); image.setImageResource(R.drawable.smile_blak);   * layout.addView(image, 0); toast.show();   *    * }   */ }}

三、程序出现的问题

   1.用户不输入名字时，点击按钮也能弹出问好的框

   2.弹出的框里的文字不能居中显示