我已將圖像按鈕放置在CardView內部的圖像視圖頂部。我想在用戶點擊圖像按鈕時觸發一些操作。然而,第一個問題是當我在MainActivity中使用findViewById獲取圖像按鈕時,它返回null(可能是因爲圖像視圖在item_row xml中,它顯示了卡片視圖中的行數據)。在卡片視圖中放置在圖像視圖中的圖像按鈕不會觸發Onclick事件
另一個問題是如何解決這種情況,其中activity_main.xml不同,其中包含具有item_row.xml圖像視圖頂部的圖像按鈕的回收站視圖。
MainActivity.java
package com.innovation.myapp.jwelleryonrent.View;
import android.graphics.drawable.Drawable;
import android.os.Bundle;
import android.support.design.widget.FloatingActionButton;
import android.support.design.widget.Snackbar;
import android.support.v4.widget.SwipeRefreshLayout;
import android.support.v7.app.AppCompatActivity;
import android.support.v7.widget.LinearLayoutManager;
import android.support.v7.widget.RecyclerView;
import android.support.v7.widget.Toolbar;
import android.view.LayoutInflater;
import android.view.View;
import android.view.Menu;
import android.view.MenuItem;
import android.view.ViewGroup;
import android.widget.Button;
import android.widget.ImageButton;
import android.widget.Toast;
import com.innovation.myapp.jwelleryonrent.R;
import com.innovation.myapp.jwelleryonrent.controller.jwelleryController;
import com.innovation.myapp.jwelleryonrent.model.adapter.CustomItemClickListner;
import com.innovation.myapp.jwelleryonrent.model.adapter.JwelleryAdapter;
import com.innovation.myapp.jwelleryonrent.model.pojo.JwelleryCollection;
import java.util.ArrayList;
import java.util.List;
public class MainActivity extends AppCompatActivity implements jwelleryController.JwelleryCallbackListener {
private Toolbar mToolbar;
private RecyclerView mRecyclerView;
private SwipeRefreshLayout mSwipeRefreshLayout;
private List<JwelleryCollection> mJwelleryList = new ArrayList<>();
private JwelleryAdapter mJwelleryAdapter;
private jwelleryController mController;
private boolean isInFavourites = false;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
configToolbar();
mController = new jwelleryController(MainActivity.this);
configViews();
ImageButton imgButton = (ImageButton) findViewById(R.id.favIcon);
imgButton.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
Snackbar.make(v, "Item Added", Snackbar.LENGTH_LONG)
.setAction("Action", null).show();
}
});
FloatingActionButton fab = (FloatingActionButton) findViewById(R.id.fab);
fab.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
Snackbar.make(view, "Replace with your own action", Snackbar.LENGTH_LONG)
.setAction("Action", null).show();
}
});
}
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState)
{
View rootView = inflater.inflate(R.layout.item_row, container, false);
ImageButton imgBtn = (ImageButton) findViewById(R.id.favIcon);
imgBtn.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
addItemToBag(v);
}
});
return rootView;
}
private void addItemToBag(View v)
{
isInFavourites = true;
ImageButton btnFaviourite = (ImageButton) findViewById(R.id.favIcon);
if(isInFavourites==true) {
btnFaviourite.setImageResource(R.drawable.ic_favorite_white_24dp);
}
else
btnFaviourite.setImageResource(R.drawable.ic_favorite_border);
Snackbar.make(v, "Item added to Favourites", Snackbar.LENGTH_LONG)
.setAction("Action", null).show();
}
private void configToolbar() {
mToolbar = (Toolbar) this.findViewById(R.id.toolbar);
setSupportActionBar(mToolbar);
}
private void initializeAdapter()
{
mJwelleryAdapter = new JwelleryAdapter(mJwelleryList);
mJwelleryAdapter.setOnItemClickListner(new CustomItemClickListner() {
@Override
public void onItemClick(View v, int position) {
Toast.makeText(MainActivity.this, "Clicked Item: "+position,Toast.LENGTH_LONG).show();
}
});
// mJwelleryAdapter = new JwelleryAdapter(mJwelleryList, new CustomItemClickListner() {
// @Override
// public void onItemClick(View v, int position) {
// Toast.makeText(MainActivity.this, "Clicked Item: "+position,Toast.LENGTH_LONG).show();
// }
// });
mRecyclerView.setAdapter(mJwelleryAdapter);
mSwipeRefreshLayout.setColorSchemeColors(getResources().getColor(R.color.colorAccent),
getResources().getColor(R.color.colorPrimary),
getResources().getColor(R.color.colorPrimaryDark));
mSwipeRefreshLayout.setOnRefreshListener(new SwipeRefreshLayout.OnRefreshListener() {
@Override
public void onRefresh() {
mController.startFetching();
}
});
}
private void configViews() {
mRecyclerView = (RecyclerView) this.findViewById(R.id.list);
mSwipeRefreshLayout = (SwipeRefreshLayout) this.findViewById(R.id.swipe);
mRecyclerView.setHasFixedSize(true);
mRecyclerView.setLayoutManager(new LinearLayoutManager(MainActivity.this));
mRecyclerView.setRecycledViewPool(new RecyclerView.RecycledViewPool());
mController.startFetching();
initializeAdapter();
// mJwelleryAdapter= new JwelleryAdapter(mJwelleryList);
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.menu_main, menu);
return true;
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle action bar item clicks here. The action bar will
// automatically handle clicks on the Home/Up button, so long
// as you specify a parent activity in AndroidManifest.xml.
int id = item.getItemId();
//noinspection SimplifiableIfStatement
if (id == R.id.action_settings) {
return true;
}
return super.onOptionsItemSelected(item);
}
@Override
public void onFetchStart() {
}
@Override
public void onFetchProgress(JwelleryCollection jwellery) {
mJwelleryAdapter.addJwellery(jwellery);
}
@Override
public void onFetchProgress(List<JwelleryCollection> jwelleryList) {
}
@Override
public void onFetchComplete() {
mSwipeRefreshLayout.setRefreshing(false);
}
@Override
public void onFetchFailure() {
}
}
activity_main.xml中
<?xml version="1.0" encoding="utf-8"?>
<android.support.design.widget.CoordinatorLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:fitsSystemWindows="true"
tools:context=".MainActivity">
<android.support.design.widget.AppBarLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:theme="@style/AppTheme.AppBarOverlay">
<android.support.v7.widget.Toolbar
android:id="@+id/toolbar"
android:layout_width="match_parent"
android:layout_height="?attr/actionBarSize"
android:background="?attr/colorPrimary"
app:popupTheme="@style/AppTheme.PopupOverlay"
android:elevation="8dp"/>
</android.support.design.widget.AppBarLayout>
<include layout="@layout/content_main" />
<android.support.design.widget.FloatingActionButton
android:id="@+id/fab"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="bottom|end"
android:layout_margin="@dimen/fab_margin"
android:src="@android:drawable/ic_dialog_email" />
</android.support.design.widget.CoordinatorLayout>
item_row.xml其中含有關於圖像查看頂部圖像按鈕(ID =圖標)。我想觸發行動的favicon
<?xml version="1.0" encoding="utf-8"?>
<android.support.v7.widget.CardView xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:card_view="http://schemas.android.com/apk/res-auto"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_margin="8dp"
card_view:cardCornerRadius="1dp"
>
<RelativeLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:padding="8dp"
android:layout_margin="5dp"
>
<ImageView
android:id="@+id/flowerImage"
android:layout_width="match_parent"
android:layout_height="200dp"
android:layout_alignParentLeft="true"
android:layout_alignParentStart="true"
android:layout_alignParentTop="true"
android:visibility="visible"/>
<ImageButton
android:id="@+id/favIcon"
android:layout_width="32dp"
android:layout_height="32dp"
android:scaleType="fitXY"
android:layout_margin="5dp"
android:layout_alignParentRight="true"
android:layout_alignParentTop="true"
android:background="@drawable/ic_favorite_border"
/>
<LinearLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_below="@+id/flowerImage"
android:orientation="vertical"
>
<TextView
android:id="@+id/flowerName"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Medium Text"
android:textColor="@color/colorPrimary"
android:textAppearance="?android:attr/textAppearanceMedium"
/>
<TextView
android:id="@+id/flowerCategory"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Small Text"
android:layout_alignBottom="@id/flowerName"
android:textAppearance="?android:attr/textAppearanceSmall"
android:visibility="visible"/>
<TextView
android:id="@+id/flowerPrice"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignBottom="@id/flowerCategory"
android:text="New Text"
android:visibility="visible"/>
<TextView
android:id="@+id/flowerInstruction"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:visibility="gone"
android:text="New Text"
/>
</LinearLayout>
</RelativeLayout>
</android.support.v7.widget.CardView>
代碼ViewHolder類,
public class Holder extends RecyclerView.ViewHolder {
public TextView mName, mCategory, mPrice, mInstructions;
public ImageView mImage;
public Holder(View itemView) {
super(itemView);
mImage = (ImageView) itemView.findViewById(R.id.flowerImage);
mName = (TextView) itemView.findViewById(R.id.flowerName);
mCategory = (TextView) itemView.findViewById(R.id.flowerCategory);
mPrice = (TextView) itemView.findViewById(R.id.flowerPrice);
mInstructions = (TextView) itemView.findViewById(R.id.flowerInstruction);
ImageButton imgButton = (ImageButton) itemView.findViewById(R.id.favIcon);
imgButton.setOnClickListener(new View.OnClickListener(){
@Override
public void onClick(View v) {
addItemToBag(v);
}
});
}
public Holder(View itemView,int ViewType,Context c) {
// Creating ViewHolder Constructor with View and viewType As a parameter
super(itemView);
}
你提的問題是非常不清楚,你爲什麼用引號?只需寫純文本。您發佈的所有內容都是xml,但您聲明您的'onClick'不起作用,因爲'findViewById'爲空。發佈您的實際代碼。你的'ImageButton'爲null的原因很可能是因爲你在你的'Activity'中調用它,但是你在適配器中膨脹視圖。 – Pztar
@Vimal你可以分享你設置onClickListener爲imageButton的Java代碼? –
這裏是MainActivity.java的代碼onCreate ImageButton imgButton =(ImageButton)findViewById(R.id.favIcon); //這裏我得到imgButton爲空 imgButton.setOnClickListener(新View.OnClickListener(){ @覆蓋 公共無效的onClick(視圖v){ Snackbar.make(V 「產品加入」,Snackbar.LENGTH_LONG) .setAction(「Action」,null).show(); } }); – Vimal