我想做的是在LinearLayout的背景上产生恒定的波纹效果。为什么?基本上,此LinearLayout指示实时用户正在观看此项目。因此,我希望背景具有恒定的波纹动画,类似于某些具有实时指示器且该指示器的背景具有波纹效果的应用程序。我希望我的问题很清楚。
例:
我希望这种效果不断出现
最佳答案
嗨,我试图编写类似这样的代码,以下是我所接近的代码。您总是可以每周增加数字,以减慢动画等速度。
1)在 res /可绘制名为 temp_ripple.xml 中创建波纹可绘制背景
<?xml version="1.0" encoding="utf-8"?>
<ripple xmlns:android="http://schemas.android.com/apk/res/android"
android:color="@color/colorPrimary"
>
<item android:id="@android:id/mask"
android:drawable="@android:color/holo_green_dark"
>
</item>
<item
android:drawable="@android:color/holo_orange_dark">
</item>
</ripple>
2)将背景分配给可能的候选 View ,如下所示,此处将AppCompatButton设置为
android:background="@drawable/temp_ripple"
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical">
<androidx.appcompat.widget.AppCompatButton
android:id="@+id/btnLive"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_centerInParent="true"
android:layout_gravity="center"
android:background="@drawable/temp_ripple"
android:foreground="?selectableItemBackground"
android:text="12.5k Live"
android:textColor="@android:color/white" />
</RelativeLayout>
3)从 View 中获取涟漪图可绘制,并在2秒后创建可运行的运行,以通过在按钮的单击侦听器中设置涟漪图可绘制的状态来重复动画
package com.example.android.treasureHunt
import android.content.res.ColorStateList
import android.graphics.drawable.RippleDrawable
import android.os.Build
import android.os.Bundle
import android.os.Handler
import android.util.Log
import android.view.MotionEvent
import android.view.View
import androidx.annotation.RequiresApi
import androidx.appcompat.app.AppCompatActivity
import kotlinx.android.synthetic.main.temp_activity.*
class TempActivity : AppCompatActivity(R.layout.temp_activity) {
val handler = Handler()
lateinit var runnable: Runnable
var count = 0
lateinit var rippleDrawable: RippleDrawable
@RequiresApi(Build.VERSION_CODES.LOLLIPOP)
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
rippleDrawable = btnLive.background as RippleDrawable
setLiveCountListener()
btnLive.setOnClickListener {
Log.d("TAG++", "button clicked")
rippleDrawable.state = intArrayOf(
android.R.attr.state_pressed,
android.R.attr.state_enabled
)
}
}
private fun setLiveCountListener() {
runnable = Runnable {
rippleDrawable.state = intArrayOf()
btnLive.performClick()
//to perform another runnable after some time creating a race condition
handler.postDelayed(runnable, 2000)
//condition to breakout from loop
if (count == 10) {
handler.removeCallbacks(runnable)
}
Log.d("TAG++", "Loop running")
}
//trigger the start of the ui thread
handler.postDelayed(runnable, 2000)
}
}