以编程方式添加SwitchCompat错误 [英] Adding SwitchCompat programmatically error

问题描述

我正在尝试以编程方式添加android.support.v7.widget.SwitchCompat，并且出现此错误:

I'm trying to add android.support.v7.widget.SwitchCompat programmatically and I'm getting this error:

java.lang.NullPointerException: Attempt to invoke interface method 'int java.lang.CharSequence.length()' on a null object reference
at android.text.StaticLayout.<init>(StaticLayout.java:422)
at android.support.v7.widget.SwitchCompat.makeLayout(SwitchCompat.java:602)
at android.support.v7.widget.SwitchCompat.onMeasure(SwitchCompat.java:526)
at android.view.View.measure(View.java:18799)
at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5951)
at android.widget.LinearLayout.measureChildBeforeLayout(LinearLayout.java:1458)
at android.widget.LinearLayout.measureVertical(LinearLayout.java:746)
at android.widget.LinearLayout.onMeasure(LinearLayout.java:629)
at android.view.View.measure(View.java:18799)
at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5951)
at android.widget.LinearLayout.measureChildBeforeLayout(LinearLayout.java:1458)
at android.widget.LinearLayout.measureVertical(LinearLayout.java:746)
at android.widget.LinearLayout.onMeasure(LinearLayout.java:629)
at android.view.View.measure(View.java:18799)
at android.support.v7.widget.Toolbar.measureChildCollapseMargins(Toolbar.java:1218)
at android.support.v7.widget.Toolbar.onMeasure(Toolbar.java:1326)
at android.view.View.measure(View.java:18799)
at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5951)
at android.widget.LinearLayout.measureChildBeforeLayout(LinearLayout.java:1458)
at android.widget.LinearLayout.measureVertical(LinearLayout.java:746)
at android.widget.LinearLayout.onMeasure(LinearLayout.java:629)
at android.support.design.widget.AppBarLayout.onMeasure(AppBarLayout.java:199)
at android.view.View.measure(View.java:18799)
at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5951)
at android.support.design.widget.CoordinatorLayout.onMeasureChild(CoordinatorLayout.java:668)
at android.support.design.widget.AppBarLayout$Behavior.onMeasureChild(AppBarLayout.java:888)
at android.support.design.widget.AppBarLayout$Behavior.onMeasureChild(AppBarLayout.java:652)
at android.support.design.widget.CoordinatorLayout.onMeasure(CoordinatorLayout.java:733)
at android.view.View.measure(View.java:18799)
at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5951)
at android.widget.FrameLayout.onMeasure(FrameLayout.java:194)
at android.support.v7.widget.ContentFrameLayout.onMeasure(ContentFrameLayout.java:135)
at android.view.View.measure(View.java:18799)
at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5951)
at android.widget.LinearLayout.measureChildBeforeLayout(LinearLayout.java:1458)
at android.widget.LinearLayout.measureVertical(LinearLayout.java:746)
at android.widget.LinearLayout.onMeasure(LinearLayout.java:629)
at android.view.View.measure(View.java:18799)
at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5951)
at android.widget.FrameLayout.onMeasure(FrameLayout.java:194)
at android.view.View.measure(View.java:18799)
at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5951)
at android.widget.LinearLayout.measureChildBeforeLayout(LinearLayout.java:1458)
at android.widget.LinearLayout.measureVertical(LinearLayout.java:746)
at android.widget.LinearLayout.onMeasure(LinearLayout.java:629)
at android.view.View.measure(View.java:18799)
at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5951)
at android.widget.FrameLayout.onMeasure(FrameLayout.java:194)
at com.android.internal.policy.PhoneWindow$DecorView.onMeasure(PhoneWindow.java:2899)
at android.view.View.measure(View.java:18799)
at android.view.ViewRootImpl.performMeasure(ViewRootImpl.java:2108)
at android.view.ViewRootImpl.measureHierarchy(ViewRootImpl.java:1224)
at android.view.ViewRootImpl.performTraversals(ViewRootImpl.java:1460)
at android.view.ViewRootImpl.doTraversal(ViewRootImpl.java:1115)
at android.view.ViewRootImpl$TraversalRunnable.run(ViewRootImpl.java:6023)
at android.view.Choreographer$CallbackRecord.run(Chore

但是当我使用Switch时，一切正常.为什么会这样呢?这是我的代码:

but when I'm using Switch everything is ok. why is this happening? this is my code:

SwitchCompat switchBox = (SwitchCompat) LayoutInflater.from(getApplicationContext()).inflate(R.layout.checkbox, null);
switchBox.setId(i);
Typeface typeface = Typeface.createFromAsset(getAssets(), "iransansfont.ttf");
switchBox.setText(convert_num((nodesModelArrayList.get(i).type ? "بیمارستان " : "مطب ") + nodesModelArrayList.get(i).node_name + ": " + nodesModelArrayList.get(i).stat));
switchBox.setTypeface(typeface);
switchBox.setOnCheckedChangeListener(onCheckedChangeListener);
linearLayout.addView(switchBox);
switchBox.setChecked(true);

推荐答案

使用活动上下文而非应用程序上下文来夸大视图，以便例如主题有效.

Use an activity context and not application context for inflating views so that e.g. themes work.

崩溃是因为textOn和textOff标签为null，通常可以从主题获取其默认值.

The crash is because the textOn and textOff labels are null that would normally get their default values from a theme.

这篇关于以编程方式添加SwitchCompat错误的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！