Android Audio代码分析24 - AudioEffect::setEnabled函数
之前已经看过，通过接口getEnabled可以取得effect的enable状态。
今天来看看如何来改变enable状态。
*****************************************源码*************************************************
//Test case 2.0: test setEnabled() and getEnabled() in valid state
@LargeTest
public void test2_0SetEnabledGetEnabled() throws Exception {
boolean result = false;
String msg = "test2_0SetEnabledGetEnabled()";
try {
AudioEffect effect = new AudioEffect(AudioEffect.EFFECT_TYPE_EQUALIZER,
AudioEffect.EFFECT_TYPE_NULL,
0,
0);
assertNotNull(msg + ": could not create AudioEffect", effect);
try {
effect.setEnabled(true);
assertTrue(msg + ": invalid state from getEnabled", effect.getEnabled());
effect.setEnabled(false);
assertFalse(msg + ": invalid state to getEnabled", effect.getEnabled());
result = true;
} catch (IllegalStateException e) {
msg = msg.concat(": setEnabled() in wrong state");
} finally {
effect.release();
}
} catch (IllegalArgumentException e) {
msg = msg.concat(": Equalizer not found");
loge(msg, ": Equalizer not found");
} catch (UnsupportedOperationException e) {
msg = msg.concat(": Effect library not loaded");
loge(msg, ": Effect library not loaded");
}
assertTrue(msg, result);
}
**********************************************************************************************
源码路径：
frameworks\base\media\tests\mediaframeworktest\src\com\android\mediaframeworktest\functional\MediaAudioEffectTest.java
#######################说明################################
//Test case 2.0: test setEnabled() and getEnabled() in valid state
@LargeTest
public void test2_0SetEnabledGetEnabled() throws Exception {
boolean result = false;
String msg = "test2_0SetEnabledGetEnabled()";
try {
AudioEffect effect = new AudioEffect(AudioEffect.EFFECT_TYPE_EQUALIZER,
AudioEffect.EFFECT_TYPE_NULL,
0,
0);
assertNotNull(msg + ": could not create AudioEffect", effect);
try {
effect.setEnabled(true);
++++++++++++++++++++++++++++++setEnabled++++++++++++++++++++++++++++++++++
/**
* Enable or disable the effect.
* Creating an audio effect does not automatically apply this effect on the audio source. It
* creates the resources necessary to process this effect but the audio signal is still bypassed
* through the effect engine. Calling this method will make that the effect is actually applied
* or not to the audio content being played in the corresponding audio session.
*
* @param enabled the requested enable state
* @return {@link #SUCCESS} in case of success, {@link #ERROR_INVALID_OPERATION}
* or {@link #ERROR_DEAD_OBJECT} in case of failure.
* @throws IllegalStateException
*/
// 创建一个audio effect，它并不会自发发挥作用。
// 该函数可以启动/停止该audio effect发挥作用。
public int setEnabled(boolean enabled) throws IllegalStateException {
checkState("setEnabled()");
return native_setEnabled(enabled);
++++++++++++++++++++++++++++++android_media_AudioEffect_native_setEnabled++++++++++++++++++++++++++++++++++
static jint
android_media_AudioEffect_native_setEnabled(JNIEnv *env, jobject thiz, jboolean enabled)
{
// retrieve the AudioEffect object
AudioEffect* lpAudioEffect = (AudioEffect *)env->GetIntField(
thiz, fields.fidNativeAudioEffect);
if (lpAudioEffect == NULL) {
jniThrowException(env, "java/lang/IllegalStateException",
"Unable to retrieve AudioEffect pointer for enable()");
return AUDIOEFFECT_ERROR_NO_INIT;
}
补充：移动开发 , Android ,
