Android 抛物线动画

package com.example.testpicture; import android.animation.Keyframe; import android.animation.ObjectAnimator; import android.animation.PropertyValuesHolder; import android.app.Activity; import android.os.Bundle; import android.view.View; import android.view.View.OnClickListener; import android.view.ViewGroup.LayoutParams; import android.view.animation.BounceInterpolator; import android.view.inputmethod.EditorInfo; import android.widget.Button; import android.widget.EditText; import android.widget.ImageView; import android.widget.LinearLayout; import android.widget.TextView; import com.example.model.ParabolaAlgorithm; public class MainActivity extends Activity { @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); LinearLayout layout = new LinearLayout(this); layout.setLayoutParams(new LayoutParams(LayoutParams.MATCH_PARENT, LayoutParams.MATCH_PARENT)); layout.setPadding(0, 100, 0, 0); layout.setOrientation(LinearLayout.VERTICAL); final ImageView imageView = new ImageView(this); imageView.setImageResource(R.drawable.face_0_063); LinearLayout.LayoutParams params = new LinearLayout.LayoutParams(LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT); params.setMargins(0, 200, 0, 0); imageView.setLayoutParams(params); final TextView textView1 = new TextView(this); textView1.setText("第一坐标点（空格区分x y）"); layout.addView(textView1); final EditText editText1 = new EditText(this); editText1.setPadding(20, 10, 20, 10); editText1.setLayoutParams(new LinearLayout.LayoutParams(LayoutParams.MATCH_PARENT, LayoutParams.WRAP_CONTENT)); editText1.setHint("第一坐标点（空格区分x y）"); editText1.setText("6 15"); editText1.setSingleLine(); editText1.setInputType(EditorInfo.TYPE_CLASS_NUMBER); layout.addView(editText1); final TextView textView2 = new TextView(this); textView2.setText("第二坐标点（空格区分x y）"); layout.addView(textView2); final EditText editText2 = new EditText(this); editText2.setHint("第二坐标点（空格区分x y）"); editText2.setPadding(20, 10, 20, 10); editText2.setSingleLine(); editText2.setInputType(EditorInfo.TYPE_CLASS_NUMBER); editText2.setLayoutParams(new LinearLayout.LayoutParams(LayoutParams.MATCH_PARENT, LayoutParams.WRAP_CONTENT)); editText2.setText("50 70"); layout.addView(editText2); final TextView textView3 = new TextView(this); textView3.setText("第三坐标点（空格区分x y）"); layout.addView(textView3); final EditText editText3 = new EditText(this); editText3.setHint("第三坐标点（空格区分x y）"); editText3.setPadding(20, 10, 20, 10); editText3.setSingleLine(); editText3.setInputType(EditorInfo.TYPE_CLASS_NUMBER); editText3.setLayoutParams(new LinearLayout.LayoutParams(LayoutParams.MATCH_PARENT, LayoutParams.WRAP_CONTENT)); editText3.setText("120 -100"); layout.addView(editText3); Button button = new Button(this); button.setText("test"); button.setPadding(20, 10, 20, 10); button.setLayoutParams(new LinearLayout.LayoutParams(LayoutParams.MATCH_PARENT, LayoutParams.WRAP_CONTENT)); button.setOnClickListener(new OnClickListener() { @Override public void onClick(View v) { String[] string1 = editText1.getText().toString().split(" "); String[] string2 = editText2.getText().toString().split(" "); String[] string3 = editText3.getText().toString().split(" "); final float[][] points = { { Float.valueOf(string1[0]), Float.valueOf(string1[1]) }, { Float.valueOf(string2[0]), Float.valueOf(string2[1]) }, { Float.valueOf(string3[0]), Float.valueOf(string3[1]) } }; float[] value = ParabolaAlgorithm.calculate(points); a = value[0]; b = value[1]; c = value[2]; count = (int)(points[2][0] - points[0][0]); startAnimation(imageView); } }); layout.addView(button); layout.addView(imageView); setContentView(layout); } int count = 120; /** * 要start 动画的那张图片的ImageView * * @param imageView */ private void startAnimation(final ImageView imageView) { Keyframe[] keyframes = new Keyframe[count]; final float keyStep = 1f / (float) count; float key = keyStep; for (int i = 0; i < count; ++i) { keyframes[i] = Keyframe.ofFloat(key, i + 1); key += keyStep; } PropertyValuesHolder pvhX = PropertyValuesHolder.ofKeyframe("translationX", keyframes); key = keyStep; for (int i = 0; i < count; ++i) { keyframes[i] = Keyframe.ofFloat(key, -getY(i + 1)); key += keyStep; } PropertyValuesHolder pvhY = PropertyValuesHolder.ofKeyframe("translationY", keyframes); ObjectAnimator yxBouncer = ObjectAnimator.ofPropertyValuesHolder(imageView, pvhY, pvhX).setDuration(1500); yxBouncer.setInterpolator(new BounceInterpolator()); yxBouncer.start(); } float a = 0f, b = 0f, c = 0f; /** * 这里是根据三个坐标点{（0,0），（300,0），（150,300）}计算出来的抛物线方程 * * @param x * @return */ private float getY(float x) { return a * x * x + b * x + c; } }