我是Android开发的新手,当用户单击按钮进行更新时,多次更新TextView时遇到问题,它仅更新一次。我的应用程序是关于一个购物车的,用户在其中选择特定的比萨饼,特定的饮料和所需的比萨饼量,然后显示价格,但这只是第一次,我想每次在按钮“单击“ +”。
Integer total = 1;
double porcion = 3.5; //every single pizza
double bebida = 2.0; //the drink
double totalAmount = (total * porcion) + bebida;
String totalAmount2 = String.valueOf(totalAmount);
// This method increases the amount of pizzas
botonmas.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
total++;
tv1.setText(total.toString());
dinero.setText(totalAmount2);
}
});
// This method decreases the amount of pizzas
botonmenos.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
if(total > 1){
total--;
tv1.setText(total.toString());
dinero.setText(totalAmount2);
}
}
});
可变总数是所选比萨饼的数量。
您永远不会更新totalAmount2
。因此它只会显示初始值。
public void onClick(View view) {
if(total > 1){
total--;
tv1.setText(total.toString());
// update totalAmount2 before showing it! <<-------
dinero.setText(totalAmount2);
}
}
[当您致电onClicked时,您没有更新totalAmount
将此添加到您的onClick()
totalAmount = (total * porcion) + bebida;
totalAmount2 = String.valueOf(totalAmount);