java - Android Grid View 在 Android 版 kitkat 上崩溃

Question

我创建了一个 gridView 来在其中显示图像。这是我的代码:

import android.content.Context
import android.support.v7.app.AppCompatActivity
import android.os.Bundle
import android.view.View
import android.view.ViewGroup
import android.widget.*

class MainActivity : AppCompatActivity() {

override fun onCreate(savedInstanceState: Bundle?) {
    super.onCreate(savedInstanceState)
    setContentView(R.layout.activity_main)

    val gridview: GridView = findViewById(R.id.gridview)
    gridview.adapter = ImageAdapter(this)

    gridview.onItemClickListener =
            AdapterView.OnItemClickListener { parent, v, position, id ->
                Toast.makeText(this, "$position", Toast.LENGTH_SHORT).show()
            }
}

private val mThumbIds = arrayOf<Int>(
    R.drawable.sample_2, R.drawable.sample_3,
    R.drawable.sample_4, R.drawable.sample_5,
    R.drawable.sample_6, R.drawable.sample_7,
    R.drawable.sample_0, R.drawable.sample_1,
    R.drawable.sample_2, R.drawable.sample_3,
    R.drawable.sample_4, R.drawable.sample_5,
    R.drawable.sample_6, R.drawable.sample_7,
    R.drawable.sample_0, R.drawable.sample_1,
    R.drawable.sample_2, R.drawable.sample_3,
    R.drawable.sample_4, R.drawable.sample_5,
    R.drawable.sample_6, R.drawable.sample_7)

inner class ImageAdapter(private val mContext: Context) : BaseAdapter() {

    override fun getCount(): Int = mThumbIds.size

    override fun getItem(position: Int): Any? = null

    override fun getItemId(position: Int): Long = 0L

    // create a new ImageView for each item referenced by the Adapter
    override fun getView(position: Int, convertView: View?, parent: ViewGroup): View {
        val imageView: ImageView
        if (convertView == null) {
            // if it's not recycled, initialize some attributes
            imageView = ImageView(mContext)
            imageView.layoutParams = ViewGroup.LayoutParams(85, 85)
            imageView.scaleType = ImageView.ScaleType.CENTER_CROP
            imageView.setPadding(8, 8, 8, 8)
        } else {
            imageView = convertView as ImageView
        }

        imageView.setImageResource(mThumbIds[position])
        return imageView
    }
}

这是我的 xml:

<?xml version="1.0" encoding="utf-8"?>
<GridView xmlns:android="http://schemas.android.com/apk/res/android"
      android:id="@+id/gridview"
      android:layout_width="match_parent"
      android:layout_height="match_parent"
      android:columnWidth="90dp"
      android:numColumns="auto_fit"
      android:verticalSpacing="10dp"
      android:horizontalSpacing="10dp"
      android:stretchMode="columnWidth"
      android:gravity="center"
/>

问题是如果我在 android 版本 lollipop 或更高版本上运行它，它工作正常。但是在 Android 版本的 KitKat 上它会在运行时崩溃

这是 kitkat 上的 logcat:

java.lang.ClassCastException: android.view.ViewGroup$LayoutParams cannot be cast to android.widget.AbsListView$LayoutParams
    at android.widget.GridView.onMeasure(GridView.java:1046)
    at android.view.View.measure(View.java:16497)
    at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5125)
    at android.widget.FrameLayout.onMeasure(FrameLayout.java:310)
    at android.support.v7.widget.ContentFrameLayout.onMeasure(ContentFrameLayout.java:143)
    at android.view.View.measure(View.java:16497)
    at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5125)
    at android.support.v7.widget.ActionBarOverlayLayout.onMeasure(ActionBarOverlayLayout.java:401)
    at android.view.View.measure(View.java:16497)
    at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5125)
    at android.widget.FrameLayout.onMeasure(FrameLayout.java:310)
    at android.view.View.measure(View.java:16497)
    at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5125)
    at android.widget.LinearLayout.measureChildBeforeLayout(LinearLayout.java:1404)
    at android.widget.LinearLayout.measureVertical(LinearLayout.java:695)
    at android.widget.LinearLayout.onMeasure(LinearLayout.java:588)
    at android.view.View.measure(View.java:16497)
    at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5125)
    at android.widget.FrameLayout.onMeasure(FrameLayout.java:310)
    at com.android.internal.policy.impl.PhoneWindow$DecorView.onMeasure(PhoneWindow.java:2291)
    at android.view.View.measure(View.java:16497)
    at android.view.ViewRootImpl.performMeasure(ViewRootImpl.java:1916)
    at android.view.ViewRootImpl.measureHierarchy(ViewRootImpl.java:1113)
    at android.view.ViewRootImpl.performTraversals(ViewRootImpl.java:1295)
    at android.view.ViewRootImpl.doTraversal(ViewRootImpl.java:1000)
    at android.view.ViewRootImpl$TraversalRunnable.run(ViewRootImpl.java:5670)
    at android.view.Choreographer$CallbackRecord.run(Choreographer.java:761)
    at android.view.Choreographer.doCallbacks(Choreographer.java:574)
    at android.view.Choreographer.doFrame(Choreographer.java:544)
    at android.view.Choreographer$FrameDisplayEventReceiver.run(Choreographer.java:747)
    at android.os.Handler.handleCallback(Handler.java:733)
    at android.os.Handler.dispatchMessage(Handler.java:95)
    at android.os.Looper.loop(Looper.java:136)
    at android.app.ActivityThread.main(ActivityThread.java:5017)
    at java.lang.reflect.Method.invokeNative(Native Method)
    at java.lang.reflect.Method.invoke(Method.java:515)
    at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:779)
    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:595)
    at dalvik.system.NativeStart.main(Native Method)

我已经弄清楚问题是由这一行引起的:

imageView.layoutParams = ViewGroup.LayoutParams(85, 85)

我该怎么办？

Answer 1

使用 GridLayout.LayoutParams 而不是 ViewGroup.LayoutParams 它将起作用。