ios - AVSpeechSynthesizer 的暂停按钮

Question

目前我有一张带有注释的 map ，当用户点击注释时会播放音频。我想添加一个播放/暂停按钮，但它不起作用，我不确定为什么。

AVSpeechSynthesizer

- (void)mapView:(MKMapView *)mapView didSelectAnnotationView:(MKAnnotationView *)anView
{
//Get a reference to the annotation this view is for...
id<MKAnnotation> annSelected = anView.annotation;

//Before casting, make sure this annotation is our custom type
//(and not some other type like MKUserLocation)...
if ([annSelected isKindOfClass:[MapViewAnnotation class]])
{
    MapViewAnnotation *mva = (MapViewAnnotation *)annSelected;

    AVSpeechSynthesizer *synthesizer = [[AVSpeechSynthesizer alloc]init];

    AVSpeechUtterance *utterance =
    [AVSpeechUtterance speechUtteranceWithString:mva.desc];
    utterance.voice = [AVSpeechSynthesisVoice voiceWithLanguage:@"en-gb"];

    [utterance setRate:0.35];
    [synthesizer speakUtterance:utterance];
}

按钮

- (IBAction)pauseButtonPressed:(UIButton *)sender 
{
[_synthesizer pauseSpeakingAtBoundary:AVSpeechBoundaryImmediate];

}

现在当我点击它时没有任何反应。

Answer 1

use this one for pause

- (IBAction)pausePlayButton:(id)sender
    {
        if([synthesize isSpeaking]) {
            [synthesize pauseSpeakingAtBoundary:AVSpeechBoundaryImmediate];
            AVSpeechUtterance *utterance = [AVSpeechUtterance speechUtteranceWithString:@""];
            [synthesize speakUtterance:utterance];
            [synthesize pauseSpeakingAtBoundary:AVSpeechBoundaryImmediate];
        }

    }