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我想使用庫：com.edmodo.rangebar.RangeBar與ViewPager，但它會給我一個nullpointerexception，當我嘗試將其添加到viewpager中。但是當我在ViewPager外部使用它時沒有問題。片段不可選，因爲您無法將片段嵌入片段中的viewpager中。com.edmodo.rangebar.RangeBar with viewpager
<android.support.v4.view.ViewPager
android:layout_width="match_parent"
android:layout_height="wrap_content">
<LinearLayout
android:id="@+id/ll_filter_seekbar"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="horizontal">
<com.edmodo.rangebar.RangeBar
xmlns:custom="http://schemas.android.com/apk/res-auto"
android:id="@+id/rangebar"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_weight="1"
custom:tickCount="2000"
custom:tickHeight="0dp" />
</LinearLayout>
</android.support.v4.view.ViewPager>
錯誤：
java.lang.NullPointerException
at com.edmodo.rangebar.RangeBar.onDraw(RangeBar.java:265)
at android.view.View.draw(View.java:14465)
at android.view.View.draw(View.java:14350)
at android.view.ViewGroup.drawChild(ViewGroup.java:3103)
at android.view.ViewGroup.dispatchDraw(ViewGroup.java:2940)
at android.view.View.draw(View.java:14348)
at android.view.ViewGroup.drawChild(ViewGroup.java:3103)
at android.view.ViewGroup.dispatchDraw(ViewGroup.java:2940)
at android.view.View.draw(View.java:14468)
at android.support.v4.view.ViewPager.draw(ViewPager.java:2171)
at android.view.View.draw(View.java:14350)
at android.view.ViewGroup.drawChild(ViewGroup.java:3103)
at android.view.ViewGroup.dispatchDraw(ViewGroup.java:2940)
at android.view.View.draw(View.java:14348)
at android.view.ViewGroup.drawChild(ViewGroup.java:3103)
at android.view.ViewGroup.dispatchDraw(ViewGroup.java:2940)
at android.view.View.draw(View.java:14468)
at android.widget.FrameLayout.draw(FrameLayout.java:472)
at android.widget.ScrollView.draw(ScrollView.java:1603)
at android.view.View.draw(View.java:14350)
at android.view.ViewGroup.drawChild(ViewGroup.java:3103)
at android.view.ViewGroup.dispatchDraw(ViewGroup.java:2940)
at android.view.View.draw(View.java:14468)
at android.widget.FrameLayout.draw(FrameLayout.java:472)
at com.android.layoutlib.bridge.impl.RenderSessionImpl.render(RenderSessionImpl.java:584)
at com.android.layoutlib.bridge.Bridge.createSession(Bridge.java:338)
at com.android.ide.common.rendering.LayoutLibrary.createSession(LayoutLibrary.java:332)
at com.android.tools.idea.rendering.RenderService$3.compute(RenderService.java:560)
at com.android.tools.idea.rendering.RenderService$3.compute(RenderService.java:549)
at com.intellij.openapi.application.impl.ApplicationImpl.runReadAction(ApplicationImpl.java:932)
at com.android.tools.idea.rendering.RenderService.createRenderSession(RenderService.java:549)
at com.android.tools.idea.rendering.RenderService.render(RenderService.java:622)
at org.jetbrains.android.uipreview.AndroidLayoutPreviewToolWindowManager.doRender(AndroidLayoutPreviewToolWindowManager.java:585)
at org.jetbrains.android.uipreview.AndroidLayoutPreviewToolWindowManager.access$1900(AndroidLayoutPreviewToolWindowManager.java:80)
at org.jetbrains.android.uipreview.AndroidLayoutPreviewToolWindowManager$6$1.run(AndroidLayoutPreviewToolWindowManager.java:527)
at com.intellij.openapi.progress.impl.ProgressManagerImpl$2.run(ProgressManagerImpl.java:178)
at com.intellij.openapi.progress.ProgressManager.executeProcessUnderProgress(ProgressManager.java:209)
at com.intellij.openapi.progress.impl.ProgressManagerImpl.executeProcessUnderProgress(ProgressManagerImpl.java:212)
at com.intellij.openapi.progress.impl.ProgressManagerImpl.runProcess(ProgressManagerImpl.java:171)
at org.jetbrains.android.uipreview.AndroidLayoutPreviewToolWindowManager$6.run(AndroidLayoutPreviewToolWindowManager.java:522)
at com.intellij.util.ui.update.MergingUpdateQueue.execute(MergingUpdateQueue.java:320)
at com.intellij.util.ui.update.MergingUpdateQueue.execute(MergingUpdateQueue.java:310)
at com.intellij.util.ui.update.MergingUpdateQueue$2.run(MergingUpdateQueue.java:254)
at com.intellij.util.ui.update.MergingUpdateQueue.flush(MergingUpdateQueue.java:269)
at com.intellij.util.ui.update.MergingUpdateQueue.flush(MergingUpdateQueue.java:227)
at com.intellij.util.ui.update.MergingUpdateQueue.run(MergingUpdateQueue.java:217)
at com.intellij.util.concurrency.QueueProcessor.runSafely(QueueProcessor.java:238)
at com.intellij.util.Alarm$Request$1.run(Alarm.java:327)
at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:471)
at java.util.concurrent.FutureTask.run(FutureTask.java:262)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
at java.lang.Thread.run(Thread.java:744)
從PageAdapter代碼：
public class FilterPagerAdapter extends PagerAdapter {
private static final int NUM_PAGES = 1;
@Override
public int getCount() {
return NUM_PAGES;
}
@Override
public Object instantiateItem(ViewGroup container, int position) {
int resId = 0;
Tools.LOG_DEBUG("This page: " + position);
switch (position) {
case 0:
resId = R.id.page_one;
break;
}
return container.findViewById(resId);
}
@Override
public boolean isViewFromObject(View arg0, Object arg1) {
return arg0 == ((View) arg1);
}
}
您可以通過其適配器向ViewPager添加視圖，而不是直接在xml佈局中添加視圖。 – Luksprog
@Luksprog我將PageAdapter中的代碼添加到問題中。這不正常嗎？ – kevingoos
不是。從您發佈的xml中移除'LinearLayout'，這不應該在那裏。然後，在適配器的'instantiateItem（）'方法中，對於位置0，獲取對「LayoutInflater」的引用（您需要在適配器中傳遞'Context）並膨脹並返回一個保存先前移除的xml佈局'LinearLayout'（連同範圍欄）。 – Luksprog