设置可见性不起作用 imageview

Posted 2023-02-21

【中文标题】设置可见性不起作用 imageview

【英文标题】：set visibility not works imageview

【发布时间】：2013-05-01 04:51:47

【问题描述】：

如果 mysql 上的值为 1，我有 java 会更改 imageview 的可见性。所以在调试时我看到我的值很好，它必须更改 setvisibility 但它没有。

这里是我的 java 文件

package com.example.androidhive;

import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;

import org.apache.http.NameValuePair;
import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;

import android.app.ListActivity;
import android.app.ProgressDialog;
import android.content.Intent;
import android.os.AsyncTask;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.widget.AdapterView;
import android.widget.AdapterView.OnItemClickListener;
import android.widget.ImageView;
import android.widget.ListAdapter;
import android.widget.ListView;
import android.widget.SimpleAdapter;
import android.widget.TextView;

public class quoPAPIERCORD extends ListActivity 

    // Progress Dialog
    private ProgressDialog pDialog;

    // Creating JSON Parser object
    JSONParser jParser = new JSONParser();

    ArrayList<HashMap<String, String>> productsList;

    // url to get all products list
    private static String url_all_products_quo = "http://192.168.1.81/php/android/get_all_quotidiens.php";

    // JSON Node names
    private static final String TAG_SUCCESS = "success";
    private static final String TAG_PRODUCTS = "products";
    private static final String TAG_PID = "pid";
    private static final String TAG_NAME = "name";
    private static final String TAG_PRICE = "price";
    private static final String TAG_CU = "cu";

    // products JSONArray
    JSONArray products = null;

    private ImageView image_A_wrong;

    @Override
    public void onCreate(Bundle savedInstanceState) 
        super.onCreate(savedInstanceState);
        setContentView(R.layout.quotidiens);

        //initialize image view
        **image_A_wrong = (ImageView) findViewById(R.id.imageView1);**

        // Hashmap for ListView
        productsList = new ArrayList<HashMap<String, String>>();

        // Loading products in Background Thread
        new LoadAllProducts().execute();

        // Get listview
        ListView lv = getListView();

        // on seleting single product
        // launching Edit Product Screen
        lv.setOnItemClickListener(new OnItemClickListener() 

            @Override
            public void onItemClick(AdapterView<?> parent, View view,
                    int position, long id) 
                // getting values from selected ListItem
                String pid = ((TextView) view.findViewById(R.id.pid)).getText()
                        .toString();

                // Starting new intent
                Intent in = new Intent(getApplicationContext(),
                        EditProductActivity.class);
                // sending pid to next activity
                in.putExtra(TAG_PID, pid);

                // starting new activity and expecting some response back
                startActivityForResult(in, 100);
            
        );

    

    // Response from Edit Product Activity
    @Override
    protected void onActivityResult(int requestCode, int resultCode, Intent data) 
        super.onActivityResult(requestCode, resultCode, data);
        // if result code 100
        if (resultCode == 100) 
            // if result code 100 is received 
            // means user edited/deleted product
            // reload this screen again
            Intent intent = getIntent();
            finish();
            startActivity(intent);
        

    

    /**
     * Background Async Task to Load all product by making HTTP Request
     * */
    class LoadAllProducts extends AsyncTask<String, String, String> 

        /**
         * Before starting background thread Show Progress Dialog
         * */
        @Override
        protected void onPreExecute() 
            super.onPreExecute();
            pDialog = new ProgressDialog(quoPAPIERCORD.this);
            pDialog.setMessage("Loading products. Please wait...");
            pDialog.setIndeterminate(false);
            pDialog.setCancelable(false);
            pDialog.show();
        

        /**
         * getting All products from url
         * */
        protected String doInBackground(String... args) 
            // Building Parameters
            List<NameValuePair> params = new ArrayList<NameValuePair>();
            // getting JSON string from URL
            JSONObject json = jParser.makeHttpRequest(url_all_products_quo, "GET", params);

            // Check your log cat for JSON reponse
            Log.d("All Products: ", json.toString());

            try 
                // Checking for SUCCESS TAG
                int success = json.getInt(TAG_SUCCESS);

                if (success == 1) 
                    // products found
                    // Getting Array of Products
                    products = json.getJSONArray(TAG_PRODUCTS);

                    // looping through All Products
                    for (int i = 0; i < products.length(); i++) 
                        JSONObject c = products.getJSONObject(i);

                        // Storing each json item in variable
                        String id = c.getString(TAG_PID);
                        String name = c.getString(TAG_NAME);
                        String price = c.getString(TAG_PRICE);
                        String cu = c.getString(TAG_CU);
                        /////////////
                        if (cu.equals("1")) 
                            cu = "oui";
                         

                        else
                            
                               cu = "pas";
                            


                        // creating new HashMap
                        HashMap<String, String> map = new HashMap<String, String>();

                        // adding each child node to HashMap key => value
                        map.put(TAG_PID, id);
                        map.put(TAG_NAME, name);
                        map.put(TAG_PRICE, price);
                        map.put(TAG_CU, cu);

                        // adding HashList to ArrayList
                        productsList.add(map);
                    
                 else 
                    // no products found
                    // Launch Add New product Activity
                    Intent i = new Intent(getApplicationContext(),
                            NewProductActivity.class);
                    // Closing all previous activities
                    i.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
                    startActivity(i);
                
             catch (JSONException e) 
                e.printStackTrace();
            



            return null;
        

        /**
         * After completing background task Dismiss the progress dialog
         * **/


        protected void onPostExecute(String file_url) 

            // dismiss the dialog after getting all products
            pDialog.dismiss();
            // updating UI from Background Thread
            runOnUiThread(new Runnable() 
                public void run() 
                    /**
                     * Updating parsed JSON data into ListView
                     * */
                    ListAdapter adapter = new SimpleAdapter(
                            quoPAPIERCORD.this, productsList,
                            R.layout.list_item, new String[]  TAG_PID,
                                    TAG_NAME, TAG_PRICE, TAG_CU,
                            new int[]  R.id.pid, R.id.name, R.id.price, R.id.cu );
                    // updating listview

                    **if(TAG_CU.equals("pas"))
                    
                        image_A_wrong.setVisibility(View.GONE);


                    
                    else if (TAG_CU.equals("oui"))
                    
                        image_A_wrong.clearAnimation();
                        image_A_wrong.setVisibility(View.GONE);

                    **
                    setListAdapter(adapter);
                

            );

        

    

这是我的布局文件

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_
    android:layout_
    android:orientation="horizontal" 
    android:padding="5px"
    android:stretchColumns="1">

    <!-- Product id (pid) - will be HIDDEN - used to pass to other activity -->
    <TextView
        android:id="@+id/pid"
        android:layout_
        android:layout_
        android:visibility="gone" />


    <!-- Name Label -->
    <TextView
        android:id="@+id/name"
        android:layout_
        android:layout_
        android:paddingRight="10px" 
        android:textSize="17sp"
        android:layout_marginRight="10px"
        android:layout_weight="0.2"
        android:textColor="#fff"
        android:gravity="left"  />

    <!-- price Label -->
    <TextView
        android:id="@+id/price"
        android:layout_
        android:layout_
        android:paddingRight="5px" 
        android:textSize="17sp"
        android:layout_marginRight="5px"
        android:layout_weight="0.2"
        android:textColor="#C00000"
        android:gravity="left"
        android:textStyle="bold"  />

    **<ImageView
        android:id="@+id/imageView1"
        android:layout_
        android:layout_
        android:src="@drawable/quo100px"
        />**

     <TextView
        android:id="@+id/cu"
        android:layout_
        android:layout_
        android:paddingRight="5px" 
        android:textSize="17sp"
        android:layout_marginRight="5px"
        android:layout_weight="0.2"
        android:textColor="#C00000"
        android:gravity="left"
        android:textStyle="bold"  />


      <TextView
        android:id="@+id/mc"
        android:layout_
        android:layout_
        android:paddingRight="5px" 
        android:textSize="17sp"
        android:layout_marginRight="5px"
        android:layout_weight="0.2"
        android:textColor="#C00000"
        android:gravity="left"
        android:textStyle="bold"  />

      <TextView
        android:id="@+id/tel"
        android:layout_
        android:layout_
        android:paddingRight="5px" 
        android:textSize="17sp"
        android:layout_marginRight="5px"
        android:layout_weight="0.2"
        android:textColor="#C00000"
        android:gravity="left"
        android:textStyle="bold"  />

</LinearLayout>

在我的调试器上，我有 Image_A_wrong = null tks提前

【问题讨论】：

请尝试只发布相关代码。很难找到你卡在哪里了。

我的问题出在 else if 上。它因空指针异常而崩溃

@Lamouette 您找到解决方案了吗？我在尝试从我的自定义列表视图中隐藏图像视图时遇到了同样的问题。请告诉我

【参考方案1】：

检查...

if(TAG_CU.equals("pas"))
                    
                        image_A_wrong.setVisibility(View.GONE);   
                    
                    else if (TAG_CU.equals("oui"))
                    
                        image_A_wrong.clearAnimation();
                        image_A_wrong.setVisibility(View.GONE);   
                    

只需更改 ImageView -> View ;)

【参考方案2】：

尝试使用，

image_A_wrong.setVisibility(View.GONE);

【讨论】：

tks，但结果是一样的。

【参考方案3】：

首先检查您是否已映射带有变量的项目。例如：

editTextVar = (EditText) view.findViewById(R.id.car_plate_et);

可能是映射丢失了，所以您可以在设置可见性之前重新调用它。

要隐藏或显示项目，请使用：

editTextVar.setVisibility(View.VISIBLE);
editTextVar.setVisibility(View.GONE);
editTextVar.setVisibility(View.INVISIBLE);

同样的情况也适用于 ImageView。

【讨论】：

您在后台运行，因此映射可能存在问题。在设置可见性之前尝试此解决方案： final ImageView myImageView = ((ImageView) activity.findViewById(R.id.fragment_photo_image_view));

我添加了这个 image_A_wrong = (ImageView) findViewById(R.id.imageView1);但结果相同。

【参考方案4】：

请尝试 image_A_wrong.setVisibility(View.GONE);

【讨论】：

我用gone试试，还是一样。

【参考方案5】：

用这个代替你正在做的事情：

                   image_A_wrong.setVisibility(View.GONE);

这样就可以了

【参考方案6】：

  if(TAG_CU.equals("pas"))
                    
                        image_A_wrong.setVisibility(View.GONE);


                    
                    else if (TAG_CU.equals("oui"))
                    
                        image_A_wrong.clearAnimation();
                        image_A_wrong.setVisibility(View.GONE);

                    
                    setListAdapter(adapter);

【讨论】：

tks，但结果是一样的。

【参考方案7】：

在我的例子中，我使用的是带有 imageview 的动画。

我必须清除动画。然后可见性消失了。

imageView.clearAnimation(); imageView.setVisibility(View.GONE);