Question

我试图弹出一个表单，但它一直在崩溃。我的错误在哪里？

这是mainactivity.java：

package com.javacodegeeks.android.fragmentstest;

import android.os.Bundle;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.ImageView;
import android.widget.PopupWindow;
import android.widget.Toast;
import android.annotation.SuppressLint;
import android.app.ActionBar.LayoutParams;
import android.app.Activity;
import android.app.AlertDialog;
import android.app.Fragment;
import android.app.FragmentManager;
import android.app.FragmentTransaction;
import android.content.Context;
import android.content.DialogInterface;


@SuppressLint("InflateParams")
public class MainActivity extends Activity implements OnClickListener  {

    ImageView mButton1;
    Context contex;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
      super.onCreate(savedInstanceState);

      setContentView(R.layout.activity_main);

      mButton1 = (ImageView) findViewById(R.id.button1);
      mButton1.setOnClickListener(new OnClickListener() {

           @SuppressWarnings("null")
        public void onClick(View arg0) {
            LayoutInflater layoutInflater 
             = (LayoutInflater)getBaseContext()
              .getSystemService(LAYOUT_INFLATER_SERVICE);  
            View popupView = layoutInflater.inflate(R.layout.popupform, null);  
                     final PopupWindow popupWindow = new PopupWindow(
                       popupView, 
                       LayoutParams.WRAP_CONTENT,  
                             LayoutParams.WRAP_CONTENT);  

                    Button btnDbutton1 = (Button)popupView.findViewById(R.id.button1);
                    View btnbutton1 = null;
                    btnbutton1.setOnClickListener(new Button.OnClickListener(){

             @Override
             public void onClick(View v) {
              // TODO Auto-generated method stub
              popupWindow.dismiss();
             }});

                    // View btnbutton1 = null;
                    popupWindow.showAsDropDown(btnbutton1, 50, -30);


            }
      });

    }

请注意，此后还有更多内容，但它与我遇到问题的部分无关。

这是popupform.XML：

<?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="#ccffcc"
    android:orientation="vertical" >

    <EditText
        android:id="@+id/editText10"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentTop="true"
        android:layout_centerHorizontal="true"
        android:layout_marginTop="132dp"
        android:ellipsize="start"
        android:ems="12"
        android:hint="UserName"
        android:textColor="#00cd00"
        android:textColorHint="#00cd00"
        android:textStyle="normal" />

    <EditText
        android:id="@+id/editText11"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_below="@+id/editText10"
        android:layout_centerHorizontal="true"
        android:ellipsize="start"
        android:ems="12"
        android:hint="Password"
        android:textColor="#00cd00"
        android:textColorHint="#00cd00"
        android:textStyle="normal" />

    <Button
        android:id="@+id/login"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_centerInParent="true"
        android:layout_marginTop="26dp"
        android:text="LOGIN HERE"
        android:textStyle="bold" />

</RelativeLayout>

这是activity_main.xml：

<?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:orientation="vertical" >

    <RelativeLayout
        android:id="@+id/logo"
        android:layout_width="match_parent"
        android:layout_height="25dp"
        android:layout_alignParentTop="true"
        android:background="#82c346" >

        <ImageView
            android:id="@+id/imageView2"
            android:layout_width="wrap_content"
            android:layout_height="20dp"
            android:layout_alignParentLeft="true"
            android:layout_centerVertical="true"
            android:layout_marginLeft="20dp"
            android:scaleType="fitStart"
            android:src="@drawable/logo" />

    </RelativeLayout>

    <RelativeLayout
        android:id="@+id/actionBarBottom"
        android:layout_width="match_parent"
        android:layout_height="65dp"
        android:layout_alignParentBottom="true"
        android:background="#d04051" >

        <LinearLayout
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:layout_centerHorizontal="true"
            android:layout_centerVertical="true" >

            <ImageView
                android:id="@+id/button1"
                android:layout_width="match_parent"
                android:layout_height="match_parent"
                android:layout_gravity="center"
                android:layout_weight="1"
                android:onClick="selectFrag"
                android:scaleType="centerInside"
                android:src="@drawable/sign_in" >

            </ImageView>
</LinearLayout>

    </RelativeLayout>

    <RelativeLayout
        android:id="@+id/actionBarTop"
        android:layout_width="match_parent"
        android:layout_height="65dp"
        android:layout_alignParentLeft="true"
        android:layout_alignParentRight="true"
        android:layout_below="@id/logo"
        android:layout_weight="1"
        android:background="#8a40d0" >

        <LinearLayout
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:layout_centerHorizontal="true"
            android:layout_centerVertical="true" >

            <ImageView
                android:id="@+id/button3"
                android:layout_width="match_parent"
                android:layout_height="match_parent"
                android:layout_weight="1"
                android:onClick="selectFrag"
                android:scaleType="center"
                android:src="@drawable/menu_scan" />

            <ImageView
                android:id="@+id/button4"
                android:layout_width="match_parent"
                android:layout_height="match_parent"
                android:layout_weight="1"
                android:onClick="selectFrag"
                android:scaleType="center"
                android:src="@drawable/menu_menu" />

            <ImageView
                android:id="@+id/button5"
                android:layout_width="match_parent"
                android:layout_height="match_parent"
                android:layout_weight="1"
                android:onClick="selectFrag"
                android:scaleType="center"
                android:src="@drawable/menu_cart" />

        </LinearLayout>
    </RelativeLayout>

    <fragment
        android:id="@+id/fragment"
        android:name="com.javacodegeeks.android.fragmentstest.Fragment3"
        android:layout_width="match_parent"
        android:layout_height="350dp"
        android:layout_above="@id/actionBarBottom"
        android:layout_below="@id/actionBarTop"
        android:layout_centerInParent="true" />

</RelativeLayout>

Answer 1

在popView中，你没有按钮1导致

 Button btnDbutton1 = (Button)popupView.findViewById(R.id.button1);

返回null。弹出窗口xml中按钮的id为R.id.login，因此它应该是

Button btnDbutton1 = (Button)popupView.findViewById(R.id.login);

另外，摆脱

  View btnbutton1 = null;
  btnbutton1.setOnClickListener

由@PedroOlivera指出

Answer 2

由于这一行而崩溃：

Button btnDbutton1 = (Button)popupView.findViewById(R.id.button1);

您的popupform.XML没有R.id.button1按钮。

将以上行替换为以下行：

Button btnDbutton1 = (Button)popupView.findViewById(R.id.login);

android中的弹出窗口，哪里是错误的

2 个答案: